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Chocolate chip cookie base, Oreos, and gooey chocolate brownie… all in one = slutty brownies!

Slutty brownies

This idea came about a good while ago, and personally I first saw the idea from Rosie Londoner. I remember making something similar once and posting it onto Instagram, and it was my most popular photo at the time reaching above 100 likes (which was like madness at the time) – but I don’t believe I ever posted the recipe.

I could be wrong in saying where they came from, but slutty brownies have become a bit of an iconic bake. To be fair, they are actually Oreo brookies, but the name slutty brownies is so well known for what the bake is now, that people just tend to stick to it!

With a thick chocolate chip cookie layer,  oodles of Oreos, and then gooey chocolate brownies you have a bit of a winner. It’s basically everything that I love, in one. Baked together to form a gooey yet delicious layer of cookie, and Oreos, AND then gooey brownie! Literally heaven in every bite.

Cookie layer

For me, the cookie layer came about from my Rolo cookie bars (and my others, but c’mon.. Rolos!), as I just love it. My original brookie post was quite different, but I have perfected these cookie bars so much that I’ve just completely changed it up to what it is now! Also, with a highly different method for baking with the brownies – freezing the cookie dough for a bit first!

It essentially is the same recipe as my Rolo cookie bars, just with a smidge less flour, and no Rolos. I felt like the cookies could get away with being a smidge softer in these, so it’s not too much of a contrast with the brownies themselves! You want the main biscuit part to come from the Oreos instead!

Brownie layer

For the brownies, it’s essentially the same recipe as my triple chocolate brownies, but halved. You don’t need a normal batch of brownies for these, as you already have the cookie and Oreo layers! Luckily, the recipe is quite easy to halve. I wouldn’t recommend baking this amount of brownie on its own though, as that probably wouldn’t taste so good!


I realise that the name – slutty brownies – is a bit much, but it’s meant in a way because they are ‘dirty’. All your favourite bits, gooey, and smushed together. They are indulgent, delicious, and INSANE when warmed up. Not going to lie, on several occasions when I have made these, I don’t want for them to cool properly first before eating them as they are just incredible.

Serve these as the are, or with ice cream, or cream or anything really! They really are just to die for – and are so moreish. Definitely not one for those who are trying to reduce their calorie content in general – but one of these isn’t going to kill you. They will be the ultimate treat. I hope you love them! Enjoy! x

Slutty Brownies!

Chocolate chip cookie base, Oreos, and gooey chocolate brownie... all in one = slutty brownies!
Print Pin Rate
Category: Traybakes
Type: Brownies
Keyword: Brownies, Cookies, Oreos
Prep Time: 20 minutes
Cook Time: 30 minutes
Total Time: 50 minutes
Servings: 16 Pieces
Author: Jane's Patisserie


Cookie Layer

  • 115 g unsalted butter
  • 125 g light brown sugar
  • 1 medium egg
  • 1/2 tsp vanilla extract
  • 225 g plain flour
  • 1/2 tsp bicarbonate of soda
  • 1/2 tsp salt
  • 1 tbsp cornflour
  • 150 g milk chocolate chips

Oreo Layer

  • 20-25 Oreos

Brownie Layer

  • 100 g dark chocolate
  • 100 g unsalted butter
  • 2 medium eggs
  • 140 g caster sugar
  • 50 g plain flour
  • 25 g cocoa powder
  • 150 g milk chocolate chips


For the Cookie Layer

  • Beat together your butter and sugar until light and fluffy!
  • Add in the egg, and vanilla, and beat again until smooth.
  • Adding the flour, bicarbonate, salt and cornflour and beat until a cookie dough is formed!
  • Add in the chocolate chips, mix, and press into the bottom of a 9x9" square baking tin, lined with parchment paper. 
  • Freeze for 20 minutes!

For the Oreo Layer

  • Preheat your oven to 180C/160C fan
  • Cover the layer of cookie, with Oreos. I keep mine whole, and just cover them!

For the Brownie Layer

  • Melt together your dark chocolate with your butter until smooth.
  • Whisk together the eggs and sugar into a thick mousse like mixture, and then fold through the melted chocolate mix. 
  • Add in the flour, and cocoa powder, and fold through again.
  • Mix through the chocolate chips carefully, and then pour over the Oreo layer!
  • Bake the slutty brownies in the over for 25-30 minutes, or until baked through. Sometimes can take a smidge longer!
  • Leave to cool in your tin for 10 minutes, and then carefully remove and finish cooling on a wire rack. 
  • Cut up into your portions and enjoy!


  • I think it's important to freeze the cookie dough, to help the brownies bake better. It is optional however! If you want, you can put the cookie layer into the fridge for an hour instead of the freezer for 20 minutes!
  • The Oreos are optional, if you just want to make brookies then you can leave them out!
  • The cookie layer is inspired by my cookie bars, and the brownie layer is inspired by my brownies! The general idea, is inspired my Rosie Londoner! 
  • These will last for 4-5 days easily, if not longer if they aren't already eaten!

Find my other recipes on my Recipes Page!

You can find me on:

J x

© Jane’s Patisserie. All images & content are copyright protected. Do not use my images without prior permission. If you want to republish this recipe, please re-write the recipe in your own words and credit me, or link back to this post for the recipe.


  1. Shabilla on August 18, 2023 at 9:04 pm

    5 stars
    Just wow!! Turned out amazing !!!! Read through the info ahead of making and whilst they took 40 mins to cook I let them cool and then placed them into the fridge for a few hours to firm up and the result was just delicious!!!! (Adjustments I made – I didn’t have any eggs so subbed with 4 tbs of mayo ) and I didn’t have Oreo’s so used digestives instead and I will defo be making this again!!! Your recipes are the best!!

  2. Louise on July 2, 2023 at 12:42 pm

    5 stars
    Never left a review before but these were so good, followed the recipe exactly (well almost) only had large eggs. Absolutely perfect. Thankyou so much

  3. Pow on April 21, 2023 at 12:24 am

    4 stars
    Hi! Just made these for the first time thank u. My cookie layer is quite dry and cakey – I saw that the order of steps is different to your Rolo recipe, is there a reason?
    Also I realised I beat the sugar with soft butter, I forgot to melt it, could that be the reason for a more dry/cakey texture?
    Will definitely make them again and hope to improve my skills so would be great to know, thank you!!

    • Jane's Patisserie on May 3, 2023 at 8:07 am

      Hiya! Not melting the butter could definitely change it if you have overbeaten the mixture. The methods are different as they are different recipes!

  4. Ellie on April 16, 2023 at 7:21 pm

    Want to make these but make them biscoff related! Could I swap the oreos for biscoff sandwich biscuits and then use your biscoff blondies recipe for the top layer, instead of a brownie layer? And just half the blondie mix?

  5. Lois GS on July 23, 2022 at 8:27 pm

    4 stars
    Cooked for 25 mins and still raw! Currently on about 45/50 mins and not sure if cooked! Very odd!

    • Jane's Patisserie on July 25, 2022 at 11:41 am

      Hiya! When baking brownies, always bake until there is a slight wobble in the middle, and then leave them to ‘set’ in the fridge overnight! Hope this helps! x

  6. J J H on July 8, 2022 at 1:58 pm

    5 stars
    Love this recipe – is there any harm in refrigerating the cookie dough for long (like 3-4 hours)?

    • Jane's Patisserie on July 11, 2022 at 12:19 pm

      Hiya! Cookie dough lats in the fridge for up to 48 hours. Hope this helps! x

    • Francesca on October 5, 2022 at 7:34 pm

      Have made these twice. The 1st time they were a huge success and total crowd pleaser. But this time made them exactly the same, the cookie dough was a bit softer but cooked for same time and the middle of the cookie layer is still raw.
      Hoping popping them back in the oven will fix it but will unfortunately overcook the brownie.
      No idea why this has happened!

    • Jane's Patisserie on October 7, 2022 at 11:33 am

      Hiya! Have you changed any thing at all? Such as equipment, oven or ingredient brands? This can sometimes make a big difference! Hope this helps! x

  7. Bethany R on July 1, 2022 at 8:56 pm

    5 stars
    Turned out absolutely divine!! I used an 8×8 and it was *perfect* after 25 minutes. I only used maybe 12 Oreos at the most, because that’s what I had in my pantry, and a single layer worked perfectly for the space I had to utilize. Thank you SO much for using metric measurements! Lol, ever since I obtained a scale that’s all I use, and the quality of my baking has absolutely been raised a tier or two, so finding delicious recipes that I don’t have to convert is delightful. Truly delicious.

  8. Dexter on May 12, 2022 at 9:32 am

    5 stars
    Hi, love all the recipes. One thing I struggle with is getting a thick “mousse like texture” because I don’t really know what this is like? How should it look at this stage? 😊

    • Jane's Patisserie on May 17, 2022 at 1:45 pm

      Hiya! When you whisk the eggs and sugar together, it should be thick, paler, and the whisk should leave a trail for a few seconds when lifted – this is the mousse like texture! Hope this helps! x

    • Ali H on April 27, 2024 at 2:31 pm

      Can take 6-8 mins of whisking. The mixture goes pale & consistency is like thick milkshake

  9. LAURA WATSON on April 30, 2022 at 1:52 pm


    These look phenomenal, although I was sold purely by the name alone! I’m planning on doubling this recipe and making two Slutty brownies in two 9” tins for desert at a friends tonight.

    How much longer might the bake time take for two pans at the same time do you think please?

    Thank you in advance!

    • Jane's Patisserie on May 3, 2022 at 4:22 pm

      Hiya! If you have doubled the mixture and then split between two tins so each tin has the same amount as the original recipe, then baking time will stay the same! Hope this helps! x

  10. Asiyah on April 27, 2022 at 4:04 pm

    Hi, I’m wondering whether I can make the cookie layer in advance and leave it in the fridge for one or two days and then make the brownie layer and bake it… but should I leave the cookie layer in the fridge or freezer if I make it in advance? Thank you!

    • Jane's Patisserie on April 29, 2022 at 10:21 am

      Hiya! Yes absolutely – cookie dough will last up to 48 hours in the fridge! Hope this helps! x

  11. Charlotte on February 10, 2022 at 5:52 pm

    What size tin should I do this in please?

    • Jane's Patisserie on February 15, 2022 at 3:18 pm

      Hiya! As per the recipe, I use a 99″ square tin! Hope this helps! x

  12. Emily on January 25, 2022 at 6:15 pm

    5 stars
    Hi Jane! These brownies are an absolute hit! 😍🙌🏼😋 LOVE LOVE LOVE!
    I’m planning on making these into a birthday cake style! I’m making the batch as normal but splitting into a couple of 5inch round tins. Would the timings be less you reckon or the same?
    Thanks in advance

    • Jane's Patisserie on January 27, 2022 at 11:28 am

      Hiya! Yes this will make the baking time less! Hope this helps! x

  13. A&E on January 16, 2022 at 3:14 pm

    5 stars
    In oven now but gone smooth oil. THanks JANE much love from kitchen xxx

    • Cee on June 7, 2022 at 7:55 pm

      5 stars
      These are so delicious. Made them yesterday. Had no oreos so put a layer of caramel on top of the dough and then the brownie topping. Top an extra 10mins to cook but were so moist and gooey so renamed them dirty brookies. Thanks so much for the fab recipe 😋

  14. Paul on October 10, 2021 at 8:16 pm

    I have made these so many times and they are amazing! I did try and use gluten free flour as I had run out of normal flour at the time, I had some left from another bake!
    The cookie base however didn’t come out the same as normal and was more wet, should I add more flour if using gluten free if I try it again?
    Thank you 😁

    • Jane's Patisserie on November 8, 2021 at 9:44 am

      Hiya! Yes, annoyingly sometimes you may need to add a little more when using gluten free flour. Hope this helps! x

  15. Charlotte Colbeck on September 22, 2021 at 7:06 am

    5 stars
    I looove this recipe – just as much as I adore all your recipes. Jane, you are a wizard!

    I was just thinking of getting adventurous the next time I make these, do you think it’s possible to use a blondie recipe instead of the brownie one you give, in order to make a kind of “naughty” blondie?
    Which of your blondie base recipes would you suggest trying in place?

    • sue Bohana on March 3, 2022 at 10:02 pm

      Do you cover the oreo layer with greaseproof paper and bake in the oven?

    • Jane's Patisserie on March 6, 2022 at 1:27 pm

      Hiya – sorry I don’t understand? The oreos are in the middle of the brownie and cookie so you wouldn’t be able to cover them!

  16. Lonan Brigid Mooney on September 8, 2021 at 7:16 pm

    5 stars

    Just one question??

    Could I make this as a 1 and a 1/2 recipe in a 7×11 pan or double the recipe for a 9×13 pan?
    Thanks In Advance!

  17. Ellie on July 5, 2021 at 12:50 pm

    Hi Jane would you be able to do a double chocolate later cookie instead, and if so what would the flour to coca powder ratio be x?

    • Sam on January 22, 2022 at 8:01 pm

      5 stars
      Absolutely delicious 😋 big hit with with the family

  18. Stacy A on June 26, 2021 at 5:56 pm

    5 stars
    Hi there!
    I’m in USA. Do you know if “cornflour” is actually corn flour or corn starch in the USA? Also is “caster” sugar regular granulated white sugar in the USA? Thanks so much!

    • Jane's Patisserie on June 28, 2021 at 7:50 pm

      Cornflour = cornstarch and caster sugar = superfine sugar! x

    • Terri-Leigh Nichols on July 4, 2021 at 5:50 pm

      I don’t have any cornflour. Can i use extra flour?

    • Cleo on August 4, 2022 at 7:06 pm

      Was trying to figure out the same, I’m from Belgium and my translation gives me both as corn flour

    • Teresa on September 25, 2022 at 5:01 pm

      Potato starch works the same as corn flour

  19. DONNA MASTERS on June 7, 2021 at 11:43 am

    Would this work with a blondie if I half the recipe of your jammy dodger blondie?

  20. Megan Rice on May 3, 2021 at 1:32 am

    5 stars
    Hi! I’ve baked these a few times for friends and family and everybody absolutely loves them. I was just wondering, everytime I do bake them (usually longer than stated), the middle dips. Even when I do ordinary brownies the same things happen, yours are so perfectly level I’m not sure what I’m doing wrong? X

    • Jane's Patisserie on May 8, 2021 at 2:37 pm

      Hey, it can sometimes be the mixing process of the eggs and sugar, or even the oven – its hard to tell for certain xx

    • Albe on October 17, 2021 at 3:13 pm

      Mine have been in the oven for about 35 and the middle is still quite gooey! Any reason or solution for this?

  21. Amy Mallia on April 19, 2021 at 12:58 pm

    Can I use salted butter for this recipe please?

    • Jane's Patisserie on April 19, 2021 at 4:57 pm

      Hey! Yes you can xx

  22. neens on April 13, 2021 at 3:06 pm

    Hi, I made these brownies exactly as stated, however, the top of the brownie was burnt whilst the cookie was undercooked. I popped them in the fridge overnight and they firmed up a bit…

    • Jane's Patisserie on April 13, 2021 at 8:29 pm

      How strange – that sounds like your oven temp is off as people would normally have the cookie over bake!

  23. Dave on April 7, 2021 at 3:11 am

    5 stars
    So, I was checking out your recipes on YouTube and was thinking. Combine millionaire brownies and slutty brownies? Would that be too ridiculous? Millionaire slutty brownies? I think I’m going to need a deeper tin. 😁

  24. Ciara on March 27, 2021 at 11:35 am

    5 stars
    10/10 .. I multiplied the recipe x1.5 to fit a larger tin and used 1 large egg for every 1.5 medium eggs if that makes sense. Anyway, they worked out perfectly, I’ll be adding these to my bank of go-to recipes

    Thanks for another great recipe Jane & can’t wait to get my hands on your book <3

  25. Sonia on March 10, 2021 at 5:40 pm

    Hi Jane, can i bake these in a 8×8” of tin ?? Can’t wait to try it omg!!

    • Jane's Patisserie on March 10, 2021 at 7:21 pm

      The risk is that the volume is about 1/5 smaller, so it will cause it to take longer to bake and maybe not bake as well but its worth a go!

  26. Joshua on February 20, 2021 at 7:01 pm

    5 stars
    I have to admit, I went for cadbury milk chocolate instead of the dark chocolate, and even with baking longer than the recipe stated the Brownie layer was runny. I was a bit disheartened that I didn’t read it properly, but then I put it in the fridge for an hour and it was completely fine! The Brownie layer was more like a fudge and I thought it was wonderful! Loved the recipe and also love the NY cookies too!

  27. Dom on February 12, 2021 at 2:52 pm

    5 stars
    Made these today the brownie was amazing but the base turned into a fluffy base? I followed all the steps and ingredients and thought it would turn out a bit like a blondie base. It tasted amazing!!

  28. Jess Draper on February 8, 2021 at 4:58 pm

    5 stars
    I made these today and omg they are the tastiest treats I have ever baked 🤤🤤 I used milk chocolate as I had no dark and didn’t want to go out again but it worked fine the middle is just slightly more gooey but I actually love that, eaten warm with ice cream 👌🏻
    I also substituted the Oreo layer for a layer of mini eggs as they are my favourite and this is just divine 😍 thank you for this amazing recipe!

  29. Karen on February 6, 2021 at 9:40 am

    Hi can I use bourneville for the brownies? Thank you

    • Jane's Patisserie on February 6, 2021 at 3:51 pm

      I would not recommend that – you need chocolate with 70%+ cocoa content x

  30. Mon on January 30, 2021 at 5:30 pm

    This recipe looks so amazing but sadly I detest Oreos. Can you suggest another biscuit to use please 😁

  31. Trystan Fleming on January 29, 2021 at 5:51 pm

    How many calories is this?

    • Liam on February 19, 2021 at 7:40 pm

      For 1/16th it is around 500kcal

    • Ciara Shine on March 9, 2021 at 10:40 am

      415cal for 1/16th

  32. Abigail Leger on January 14, 2021 at 10:22 am

    Out of interest, why is it that hobnobs will go soft and oreos wont? x

    • Jane's Patisserie on January 14, 2021 at 12:31 pm

      No, the oreos do too… but I have to say it as some people get really funny about a biscuit going soft.

  33. Abi on January 13, 2021 at 7:19 am

    5 stars
    This recipe is amazing!
    I’m wondering if I can use hobnobs instead of Oreos on my next bake for a hobnob obsessed birthday girl? Thanks!

    • Jane's Patisserie on January 13, 2021 at 12:16 pm

      You can! Although they will go soft x

  34. Tori on January 6, 2021 at 3:27 pm

    5 stars

    I did everything you got in the recipe but the middle of the brownie is taking ages to cook, what am I doing wrong?


    • Jane's Patisserie on January 7, 2021 at 2:17 pm

      It can be a few things. What chocolate did you use for the brownie mix? x

    • Lola on February 5, 2021 at 9:16 am

      5 stars
      I found this too but noticed that as it cools it hardens

    • Laura Peveller on December 13, 2021 at 7:56 am

      Hello! Love this recipe – are these suitable to freeze?

    • Jane's Patisserie on December 14, 2021 at 11:42 am

      Yes absolutely! These can be frozen for up to 3 months! Enjoy! x

  35. Emma Horgan on January 6, 2021 at 7:06 am

    Would I be able to use marshmallow fluff instead of the Oreos? I love the smores cookie bars and wanted to make a super slutty treat

    • Jane's Patisserie on January 6, 2021 at 9:51 am

      You could try it, but it might make them bake a little weirdly!

  36. Merryn on December 13, 2020 at 2:01 pm

    4 stars
    I made these along side your nyc cookies , the cookies are amazing , however I followed every single step for the slutty brownies and after 29 minutes it was still no where near cooked , I put them back in for another 20 minutes and they have burnt on the top but after cooling are still just mixture in the middle , where could I be going wrong , I’ll definitely be giving them another go tho

    • Jane's Patisserie on December 13, 2020 at 4:19 pm

      What chocolate did you use for the base brownie mix? And how did you mix it?

    • Merryn on December 14, 2020 at 8:14 am

      I used dark chocolate and I used and electric hand whisk to mix the sugar and eggs and then folded in the dry Ingredients in , I followed every single step so I’m not sure if maybe it’s just a problem with my oven 🤷🏼‍♀️

    • Jane's Patisserie on December 14, 2020 at 10:29 am

      It can be your oven – what cocoa content was the dark chocolate? Brownies are classically annoying unfortunately! x

  37. Hannah on December 10, 2020 at 12:48 pm

    5 stars
    Hi, would it be ok to refrigerate (rather than freeze) the cookie dough before layering the Oreos and brownie mixture on top and baking? The tin won’t fit in my small freezer! If so, how long for?

    • Jane's Patisserie on December 10, 2020 at 5:31 pm

      You can do, but it may still over bake slightly as it’s not going to be as cold! x

  38. Jas on November 19, 2020 at 10:12 pm

    Hi I really want to try these, can I half the recipe to make a smaller batch ?


    • Jane's Patisserie on November 20, 2020 at 9:12 am

      Half fits about a 7″ square, but its hard to half the egg for the cookie as you only use one, and the brownie mix is going to be quite hard too as it’s such a small amount! It’s worth a go, but I can’t guarantee its the best results x

  39. Jade on November 14, 2020 at 8:56 pm

    Hi, If I made this in a cake tin instead of a square tin would I need to amend the baking time? I’m doing a work bake off and was thinking of doing this bake but make it look more like a cake. I’m not sure if it would work?

    • Jane's Patisserie on November 15, 2020 at 8:36 am

      So square tins are about the same volume as a round that is one inch bigger… so this is a 9″ square, you would need a 10″ round for it to be the closest. Smaller tins will increase baking time and may make the middle more gooey! x

    • Jade on January 8, 2021 at 11:16 pm

      Hi Jane, thank you for the advice. It worked perfectly. Everyone loved it and I ended up winning the work bake off with this 👌🏻

    • Amy on January 29, 2021 at 11:57 am

      Hi, I’ve only got a 8” square, would you recommend leaving out a portion of the mixture. These look perfect and would like very close to! Thank you

    • Jane's Patisserie on February 1, 2021 at 5:15 pm

      Typically its about 1/5 less so hard to do, you can reduce it if you want, or bake it as it is but they may be a little raw in the middle where it’s deeper x

  40. Jess on November 6, 2020 at 1:20 pm

    5 stars

    Can you use stork from a tub for this recipe (for either component)? Have made with butter before and they were amazing – but I have some stork to use up 🙂

    Thanks in advance!

  41. Suzie on November 3, 2020 at 6:59 pm

    5 stars
    So gorgeous! Family favourite

  42. Lyn on October 17, 2020 at 11:35 am

    5 stars
    Hi Jane
    Can you freeze the brownies?

    • Jane's Patisserie on October 17, 2020 at 11:50 am

      Yes you can!

    • Zoe Sheard on January 21, 2021 at 8:21 pm

      5 stars
      Hi I’ve made this today and it’s been a huge hit! Just wondering what else can I use instead of the Oreos? I love the cookie base x

    • Jane's Patisserie on January 22, 2021 at 8:53 pm

      You can basically use any biscuit!

  43. Alex on September 29, 2020 at 1:32 pm

    Hi! I done everything correct apart from freeze the cookie for 20 mins! Will this affect the end result? Its currently in the oven now

    • Jane's Patisserie on September 29, 2020 at 6:01 pm

      It certainly can change how it bakes – it’s designed to stop the cookie over baking, and also make sure the layers stay separate.

  44. vicky on September 25, 2020 at 12:03 pm

    5 stars
    Found your brill recipe page yesterday and I’ve just made a batch of these however I only had a 7×11 inch cake tin and they came out perfectly in 25 minutes. Also added a few chopped hazelnuts to the brownie layer 😋😋 will definitely be making my way through your yummy recipes, thanks Jane 😁👌

  45. Abbey on September 20, 2020 at 3:15 pm

    5 stars
    You are the queen of recipes!

  46. Screenname 1994 on August 24, 2020 at 9:38 am

    5 stars
    Wow! Why have I only just discovered your blog!
    These are absolutely incredible! My cookie layer went a tad cakey but I think that may be because I over baked them slightly, I had a bit of an oven mishap and put them in the oven for half an hour with only the light in the oven being on and not the actual oven being on 🙈

    • Jane's Patisserie on August 24, 2020 at 9:24 pm

      Ahh yes, it will just be over baked slightly – warm them in the microwave if you have one before eating and they should be fine! x

  47. Sarah on August 19, 2020 at 10:36 pm

    Hi Jane,

    I am looking to bake this over the weekend and was just wondering if I could replace the Oreo layer with a spread such as Nutella or Biscoff?

    If so and you think this would work, how much would you recommend using and would you just spread it on the cookie layer and then put the brownie on top?

    Thanks in advance!

    • Jane's Patisserie on August 20, 2020 at 10:11 am

      Yes so it should work, but sometimes can take longer to bake (I am doing a recipe for them soon) – but I would spread a layer onto the frozen cookie and then put the brownie on top! x

  48. Nas on August 18, 2020 at 2:11 pm

    Hi Jane, Can I just use your regular cookie bar recipe as I have some terrys cookie bar dough left Thank you x

    • Jane's Patisserie on August 18, 2020 at 3:40 pm

      Yes you can – this is just reduced as you want a thinner layer x

  49. Mia on August 11, 2020 at 10:42 pm

    5 stars
    I baked this recipe for the first time the other night and fed them to my family, they said they were amazing.

    But I also have some family members that couldn’t enjoy them as they are vegan and I was just wondering if you have a vegan version for this recipe as I find your recipes are the easiest and most straight forward to follow.

    Thank you 😊

  50. Farah on August 10, 2020 at 5:11 am

    Hi, Jane. Just wondering. What if I only use 1 egg in brownie batter recipe? Can I substitute with more milk?

    • Jane's Patisserie on August 10, 2020 at 9:45 am

      For the best brownie you’d use the correct ingredients in my opinion x

  51. kathleen on August 1, 2020 at 8:52 pm

    Hi Jane,

    Just wondering you dont state on your recipes if the butter will be hard/ softened/ melted.

    Thank you

    • Jane's Patisserie on August 1, 2020 at 8:54 pm

      If I don’t say anything it should just be used as is, but on the brownie section I do say to melt it.

  52. abi on July 26, 2020 at 4:05 pm

    is it okay to put the brownies mix in the fridge for a few hours before putting it into the oven?

    • Jane's Patisserie on July 26, 2020 at 5:47 pm

      generally I would say no, all recipes (bar stuff that has to prove or cookie dough) should be baked straight away x

  53. Ishana on July 22, 2020 at 4:06 pm

    Hey i was wondering if i could substitute egg in brownies with something?

    • Jane's Patisserie on July 22, 2020 at 7:10 pm

      There’s various egg replacements out there so it’s worth a google! x

  54. Paris Anysia Coldwell on July 16, 2020 at 11:46 pm

    Hey, could i swap the oreos for something chocolatey like Kinder bars to put in the middle?

    • Jane's Patisserie on July 17, 2020 at 8:33 am

      Yes! But be careful the amount you add if it’s something that’s like just chocolate as it can make it take longer to bake!

  55. RT on July 16, 2020 at 3:38 pm

    Hi Jane! If I wanted to make the cookie bar bottom chocolate how much cocoa powder would I need to add and would this need to replace some of the flour?


    • Jane's Patisserie on July 16, 2020 at 9:12 pm

      I would swap out 25g of flour for cocoa powder! x

    • victoria on June 30, 2021 at 11:03 am

      hey! love the recipe – love that i managed to get a crackly brownie top is crackly! however, the cookie base turned out more like a fluffy sponge cake and not like a cookie at all. may i know what went wrong?

    • Jane's Patisserie on July 2, 2021 at 9:36 am

      Hiya, this might mean the cookie is over baked so you will need to lower the temperature or freeze the dough for longer xx

  56. lola on July 14, 2020 at 3:46 pm

    5 stars
    Just to say you and your recipes are just AMAZING!!!

  57. Lib on July 13, 2020 at 8:36 pm

    Hi Jane, do you know if this would be possible to make with Gluten free flour?
    They look delicious 😛 x

    • Jane's Patisserie on July 14, 2020 at 5:31 pm

      Hey! Yes it should be absolutely fine! But you’d need to check all ingredients as oreos for example aren’t gluten free. x

  58. Izzy on July 8, 2020 at 9:09 am

    Hi Jane! I’m going to make these over the weekend but i only have dark brown sugar instead of light brown sugar for the cookie layer, will this work okay? Love all your recipes! x

    • Jane's Patisserie on July 8, 2020 at 6:35 pm

      Hey! Yes it will bake the same but be slightly darker in colour and flavour x

  59. Elycia on July 6, 2020 at 7:45 pm

    5 stars
    Really want to try this recipe! Was wondering how much roughly the cooking time would increase for a 7×7 inch tin? Thank you x

    • Jane's Patisserie on July 6, 2020 at 9:10 pm

      I wouldn’t recommend baking this batch into a 7″ tin as the tin is about 2/3 of the volume – personally I would make 2/3 of the recipe, and then the baking time will reduce x

  60. Jessica on July 3, 2020 at 12:36 pm

    Hey could you make these with a blonde top instead? If so, would you recommend halving one of your blondie recipes?

  61. Katie on July 3, 2020 at 12:17 pm


    Just wondering if I could make this with gluten free flour? Would it be the same quantity of everything?

    Thanks 🙂

    • Jane's Patisserie on July 3, 2020 at 4:07 pm

      Hey! So basically it is a straight swap, but the texture may be slightly different (and you’d need to make sure all ingredients are GF such as the oreos need switching to GF ones!)

  62. Jess on July 3, 2020 at 11:48 am

    5 stars
    I was so pleasantly surprised on trying this recipe! I thought maybe the three layers would make for a complicated bake but it was so simple to make and came out perfectly- looked exactly like the pictures. Think these will become a staple bake for me, also loved that there wasn’t a long list of complicated ingredients.

  63. Ceri Matthews on July 3, 2020 at 12:29 am

    Is it possible to make half brookies and 1/2 slutty brookies? I’ve looked at both recipes and their slightly different?
    Thank you

  64. Lindsay on July 2, 2020 at 8:57 pm

    Hey, these look amazing and I would like to try and make them and have them warm with some ice cream, could I heat them up at all or would I only be able to do it straight from the oven?

    • Jane's Patisserie on July 3, 2020 at 11:56 am

      You can microwave them for example for 20 seconds or so per piece as you don’t want to keep re-heating the entire batch x

  65. Lauren on June 30, 2020 at 9:51 pm

    Hey! I always use your recipes and they’re perfect, but I have a big mixing bowl and I feel like doing half the usually volume of eggs and sugar in such a big bowl didn’t make it moussey enough!

    I could sense it wasn’t thick enough (after over 5 minutes of whisking with an electric had whisk when for a normal brownie mix it takes about 3) but carried on anyway anyway and now it’s taken 45 minutes to bake 🙁 Have you got any tips?

    • Jane's Patisserie on July 1, 2020 at 2:03 pm

      What mixer do you use? I don’t usually have any problems with mine and I use a Kitchenaid – it won’t be the exact same as the quantities are less but it should still work! x

  66. Bethany on June 30, 2020 at 12:55 pm

    Hey Jane, my tray is 8 inch x 8inch, will the cooking time still be the same? Also does it matter how deep the tray is? Many thanks x

    • Jane's Patisserie on June 30, 2020 at 7:12 pm

      The depth of the tray doesn’t matter as long as it’s deep enough to contain the ingredients – but the time will increase due to the smaller tin!

    • Millie on January 9, 2021 at 4:48 pm

      Hello! I seem to be having the same problem as a few people. My brownie layer just wont bake. It’s been 40 minutes. I used dark chocolate in the mixture. Any advice? xx

    • Jane's Patisserie on January 10, 2021 at 2:08 pm

      What exact dark chocolate did you use?

  67. Ebony on June 29, 2020 at 10:56 pm

    This looks delicious and I really want to make these… But I’m vegan. Do you think swapping the egg for flaxseed will work or not? And the butter to vegan butter? Thank you Xx

  68. Tara on June 29, 2020 at 5:34 pm

    Hiya, this is such a silly question but is it 180C or 160C for a fan oven? Also I usually make my brownies with milk chocolate, but in this case would that make it much harder to bake properly?
    Made many of your other recipes and they are amazing!

    • Jane's Patisserie on June 29, 2020 at 7:22 pm

      Hiya – I really really recommend the dark chocolate for the brownie base. And I usually bake mine at 160C fan, but 180C can work too as long as your oven doesn’t run too hot! x

    • Vivian on July 28, 2020 at 6:41 pm

      Tried this for the first time and it’s a bit! I’ve doubled the recipe thinking we will eat it all but wonder if I can freeze the baked brownie and microwave when we want to eat it?

    • Jane's Patisserie on July 28, 2020 at 6:49 pm

      Hey! Yes you definitely can – I always have a brownie supply in my freezer!!

  69. Tia on June 22, 2020 at 8:37 pm

    Hi Jane! This looks amazing. I wondered if I’d be able to swap the Oreos or just leave them out and have Rolo brownies with a cookie base? Would that work or would the rolos mean they may not cook properly?

    Thank you!!!

    • Jane's Patisserie on June 22, 2020 at 9:10 pm

      Hey! So you can swap the oreos for other biscuits easily, or leave the amount! Rolo’s can definitely change baking time, but should work okay if frozen solid first! x

  70. Ellie on June 22, 2020 at 4:13 pm

    4 stars
    Made these this afternoon and they taste fab, only comment is that the cookie section has more of a cakey texture than cookie? I froze as per instructions is there something that could of caused this or is this how they should be?

  71. Tom N on June 21, 2020 at 9:54 am

    Hi Jane. I made your triple chocolate brownies, which were amazing, and now want to try these. In the recipe only milk choc chips are mentioned, but in the pictures it looks like white are used as well. I might just be being thick! Would you use white or just stick to milk? Thanks!

    • Jane's Patisserie on June 21, 2020 at 3:38 pm

      Hey! Sorry I’ve made these a few times haha – you can use either/any! In the cookie bit I did just use milk, but brownies I think I used a mix! (The oreo filling has made it look a bit like white chocolate on the bottom) x

  72. M on June 14, 2020 at 7:20 pm

    Hi Jane,
    Love your recipes! When you say bake through, should a knife be clean? I always worry if I will over bake or under bake. I know they cook more when they are in the tin but worried I take them out too early. Sometimes I don’t know if things are raw or just super gooey. Any tips you could provide would be fab
    Thanks so much 🙂 x

    • Jane's Patisserie on June 14, 2020 at 8:24 pm

      Hey! So typically the skewer test doesn’t work the best with traybakes. Because there are things inside side as the oreos, chocolate chips it can mean it may always look dirty! I usually say a small wobble in the middle, and then maybe a skewer with a few crumbs, but nothing major!

  73. Kimberley Thompson on June 8, 2020 at 12:14 pm

    Once cooked, can the brookies be frozen and defrosted to eat another day?

    Would you suggest cooking from frozen or defrost overnight?

    Thank you

    • Jane's Patisserie on June 8, 2020 at 12:35 pm

      Hey! Yes you can definitely freeze them – they just need thawing, they don’t need baking again! x

  74. Sarah on June 6, 2020 at 11:26 am

    Hi can you use any flavoured Oreos e.g brownie flavoured?

  75. Erin on June 1, 2020 at 10:39 pm

    5 stars
    I’ve made this twice and both times it was all gone in 2 days!! It’s lush!!

    I wanted to make a plan brownie could I just use the brownie layer from this recipe ?

    • Jane's Patisserie on June 2, 2020 at 11:38 am

      Hey! You can – but it’s very thin – I would look at my triple chocolate brownie post!

  76. Toni Taylor on May 26, 2020 at 4:11 pm

    Could I make the cookie later up in advance and free for 3 days before doing the full
    Brownie? I have free time today to bulk bake as much as I can but would like the brownies to be made for Friday for freshness 🤗

  77. Caz on May 22, 2020 at 3:56 pm

    3 stars
    I’m not sure on this… made them for the first time today… I had them in for about 45 mins in total, allowed them to cool but the middle of the tray is defo not cooked in regards to the brownie 😞
    How do you know when they are really ready to come out

    • Jane's Patisserie on May 24, 2020 at 1:43 pm

      Hey! So did you swap anything out for the brownie part? Such as using milk chocolate instead of dark? As that definitely causes a problem – other than that, you really do need to be careful when folding everything in, as not folding carefully, or not whising the eggs/sugar up enough can make the mixture thin – and that can cause problems! X

  78. Sarah on May 22, 2020 at 1:34 pm

    5 stars
    Made these today – they are lovely! My family loves them. Do keep them in fridge once done please?

    • Jane's Patisserie on May 22, 2020 at 8:07 pm

      Ahh yay! I just keep them at room temp personally! x

    • Kimberley Thompson on June 8, 2020 at 10:45 am

      Once cooked, can the brookies be frozen and defrosted to eat another day?

  79. Emily on May 17, 2020 at 3:27 pm

    5 stars
    I’ve made this twice now I love it and I have made several other recipes the are sooo good.♥️

    • Nat on May 29, 2020 at 9:07 am

      Would it work to use white chocolate chips instead of milk ones as struggling to get hold of them at the moment?

      Thank you 🙂

    • Jane's Patisserie on May 29, 2020 at 9:11 am

      Hey! Yes for sure – you can swap up the chocolate chip flavour!

    • Manmeet Edwards on August 21, 2020 at 9:03 pm

      5 stars
      My passion is baking and i love making brownies, I normally have a standard recipe I use but I came across these and now will never use another one again.
      They were an instant hit and I made them both ways with and without oereos definitely prefer the oreo addition they didn’t last long and I took some for my sister in law and nephew and they loved them 😁

  80. Kathryn Jade on May 3, 2020 at 9:03 pm

    4 stars
    I wasn’t sure how I felt about this recipe, but I thought I would give it a go either way as what is the worst that can happen when you combine cookie mixture and brownies?
    I was pleasantly surprised at how these turned out and although I won’t be baking them regularly, they are definitely one to bake if you want an indulgent pudding!

  81. H on May 3, 2020 at 8:25 pm

    5 stars
    These were wonderful and the recipe was really easy to follow! 😊

  82. Morgan on May 3, 2020 at 8:02 pm

    5 stars
    Have made 4 batches of this to deliver to friends during lockdown. Great recipe, have only tried without the Oreos, but simply delicious!

    • Sarah on June 30, 2020 at 9:52 am

      Hi these look amazing – can they be made dairy free? Thanks

    • Jane's Patisserie on June 30, 2020 at 7:15 pm

      Yes! The butter can be dairy free spread, I use stork block, and then swap the chocolates to dairy free versions!

    • Danny on March 6, 2022 at 5:25 pm

      Hi how much do it work out per piece.

  83. Zak hoblyn on May 2, 2020 at 7:55 am

    5 stars
    Wohooo, These came out great!!! I am not usually a fan of Oreos but it really adds a nice flavour. Recipe and timings were perfect, it also looks soo impressive!
    Definitely freeze the cookie dough as Jane says before applying the brownie mixture.

  84. Danielle on April 20, 2020 at 1:18 pm

    Hi, are there any other types of sugar I could use for the cookie layer, I can’t find light brown sugar anywhere!!! Thanks x

    • Jane's Patisserie on April 20, 2020 at 1:38 pm

      It’s best to use something like granulated sugar, but caster sugar can be used if needed.

  85. Alex Groves on March 18, 2020 at 6:23 pm

    Hi trying this recipe for first time tonight and brownie still seems to be very sloppy after 30mins in oven? Any suggestions please?

    • Jane's Patisserie on March 18, 2020 at 7:15 pm

      As mentioned on the post, it can take a little while in some ovens – however, it really does rely on using the correct ingredients (such as dark chocolate) and whisking correctly, so it could be any number of reasons. As it’s such a thin layer though – half the normal amount – they should be fine once cooled!

  86. Charlotte on March 4, 2020 at 11:34 pm

    5 stars
    Wow what an amazing recipe. This was a hit with everyone – especially a friend who loves brownies. I’ll be making these again next week!

  87. Lucy on March 2, 2020 at 5:28 pm

    Looks amazing!
    Do you think it would work to double to recipe and cook in a 9×13″ tin? Would the baking time change much?

    • Jane's Patisserie on March 2, 2020 at 5:36 pm

      A 9×13″ tin is roughly 1.4x the size of my suggested tin, so it might take a bit longer!

  88. Lou Cox on February 26, 2020 at 7:49 pm

    Hi, this recipe looks great. Do you have a view on what cocoa content chocolate you would use or at least the minimum percentage that you would recommend? Many thanks Lou

    • Jane's Patisserie on February 26, 2020 at 10:30 pm

      Generally it should always be 70% or darker, but I recommend 80% or more!

  89. Poppy on January 21, 2020 at 1:10 pm

    Can I freeze these?

  90. A B on December 3, 2019 at 9:24 pm

    hi I’m making this for my birthday, I was just wondering if it was okay to leave the cookie layer in the fridge over night or maybe even a couple of nights?? also do you have any other suggestions for what you could put instead of the oreo layer(anything really) (I love oreos but there not usually my first choice))

    • Jane's Patisserie on December 7, 2019 at 8:36 pm

      I would follow the recipe and freeze the cookie dough for the best results, it would last ages in the freezer – and you can swap for pretty much any biscuit!

  91. Sarah on October 13, 2019 at 5:12 pm

    Made these today – they are amazing!!

  92. Demi Young on July 13, 2019 at 8:39 am

    Are these ok to freeze and then defrost? Xx

  93. Demi Young on July 3, 2019 at 6:44 am

    Hi lovely. Last time I tried to making the slutty brownies, the cookie part completely burnt. Can you help at all? Xxxx

    • Jane's Patisserie on July 3, 2019 at 5:40 pm

      Did you bake them for longer than the timings stated? If not, it’s very surprising that they managed to burn – there may be something wrong with your oven!

  94. Samantha on June 24, 2019 at 2:49 pm

    Hi Jane,
    I don’t have any cornflour. Is there anything I can use to substitute it?

    • Jane's Patisserie on June 24, 2019 at 4:50 pm

      Cornflour really is the best thing for it – but if you really can’t use it you can take it out and add in 50g more flour (the bake may still be different)

    • Beth on March 15, 2020 at 9:57 am

      5 stars
      These were amazing! Made them yesterday with a friend and they are super scrummy. Question: can you use the cookie recipe part to make normal cookies? Thank you! Xx

    • Jane's Patisserie on March 15, 2020 at 12:41 pm

      You can! But have a look at my cookie bar recipes as thats purely cookie based!

  95. Tammy on June 17, 2019 at 9:22 pm

    Hiya, might be a silly question but what size tin do you use for this recipe? Thank you.

    • Jane's Patisserie on June 18, 2019 at 7:29 am

      It’s written in the method – but its a 9″ square.

    • Zohra on June 14, 2023 at 3:45 pm

      5 stars
      Love love this recipe and so does everyone that’s had them! I need to bake this for Saturday but was wondering if I could mbake them tomorrow in advance? Would they be okay? Got cakes to bake on Saturday so trying to make it easier 🙈 x

    • Jane's Patisserie on June 19, 2023 at 11:27 am

      Hiya! Yes they would be fine – you can freeze them or store them in the fridge x

  96. Jacob Hardman on June 15, 2019 at 3:09 pm

    Maybe a silly question but if I wanted to make more at once is it possible just multiple all the ingredients by 1.5 or 2?

    • Jane's Patisserie on June 15, 2019 at 4:04 pm

      You could, but I would advise using a larger tin as well – if you doubled it, you could bake into a 9×13″ tin!

  97. Naomi on April 17, 2019 at 11:10 am

    5 stars
    Hi Jane
    Have made these once already and am about to make another 2 batches for people at work as they loved them. Do you think mini eggs would work in place of the Oreo layer? Thank you for the awesome recipes Naomi

    • Jane's Patisserie on April 17, 2019 at 4:38 pm

      Yessss, I’ve done this and it’s epic!

    • Naomi on April 25, 2019 at 1:18 pm

      Thank you Jane tried it and was awesome ☺☺☺☺

    • Kim on May 14, 2020 at 5:53 pm

      5 stars
      Hi, I have no parchment paper, any suggestions what I can do instead please?

    • Jane's Patisserie on May 15, 2020 at 9:27 am

      Hey! I really do recommend lining tins with parchment/greaseproof paper I’m afraid!

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