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Easy and fudgey Mars Bar brownies! So chocolatey, so delicious!

Mars Bars brownies

It’s the time to have something so chocolatey, that you’ll want to make them again and again. These Mars Bar brownies is exactly that. So unbelievably chocolatey and fudgey they are on a next level. Are you intrigued yet?

Anyway. I thought I would start this recipe post off with a statement that makes you go these MUST be good, and then you’ll see the pictures and be like oh heyyy look at them, yes, they are amazing. And I really hope you guys did because I certainly did. 

Mars bars and Milkyway bars (US)

From the beginning I must say that Mars Bars in the UK, are Milkyway bars in the US, so if some of my American readers are a little confused right now, just roll with a Milkyway instead. I finally found out why there is a different in name the other day (due to a family spat back in the day), and I was surprised that that was all it was. 

Even so, Mars Bars are the one. They are slightly underrated in my opinion, but I do adore them. For those who have never experienced the wonder that is a Mars Bar… they are nougat and caramel, coated in milk chocolate. They are delightful. 

Mars Bar recipes

When I was thinking about what chocolate bars I should bake with, I wanted to use one I hadn’t tried in a while. I’ve used Mars Bars four times on this blog already, my favourite time being my Mars Bar cheesecake, but it was so long ago! 

These brownies came about because of my craving for something Mars Bar, and also because they were on offer in the supermarket I was in at the time so that made the bake cheaper. Always handy in my books. I couldn’t resist! 

Dark chocolate

I went for a classic style brownie, that I have used in so many recipe posts now. And I will say it time and time again, PLEASE USE DARK CHOCOLATE IN THE BROWNIE MIXTURE. I don’t really care if you ‘don’t like dark chocolate’ it will make such a good brownie, and not too ‘dark’ a flavour, so PLEASE stick with it. 

If you use milk chocolate, the mixture is so much thinner, and when people moan to me that their brownies didn’t bake properly, and say they switched to milk chocolate then that is why. It doesn’t work the same, and doesn’t make them nearly as fudgey. Dark chocolate is the best. 

Brownie

The key really is to make the brownie mixture as thick as possible, and dollop on all your Brownie bits. When the caramel and nougat bakes, it’ll make little pockets of deliciousness for you to enjoy, and they are just a combination to behold. SO tasty!

Freezing Mars Bars

I realise its a faff, but freezing the Mars Bar bits before baking really is the best practice so they don’t explode everywhere completely and utterly, but its not completely essential. However, if you can, I would 100% recommend it! 

These brownies are so fudgey, so moreish, and delightful. I really hope they live up to your expectations for my latest Mars Bar creation! Enjoy! X

Mars Bar Brownies

Mars Bar Brownies!

Easy and fudgey Mars Bar brownies! So chocolatey, so delicious!
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Category: Traybakes
Type: Brownies
Keyword: Mars Bar
Prep Time: 15 minutes
Cook Time: 25 minutes
Cooling Time: 1 hour
Total Time: 1 hour 35 minutes
Servings: 16 Pieces
Author: Jane's Patisserie

Ingredients

Brownies

  • 200 g dark chocolate
  • 200 g unsalted butter
  • 3 large eggs (or 4 medium)
  • 275 g light brown sugar
  • 100 g plain flour
  • 50 g cocoa powder
  • 300 g Mars Bar (chopped & frozen)
  • 100 g milk chocolate chips (optional)

Optional Decoration

  • 50 g milk chocolate (melted)
  • Mars Bar pieces

Instructions

  • Preheat your oven to 180C/160C Fan and line a 9x9" baking tin with parchment paper!
  • Melt together your dark chocolate and unsalted butter until smooth in the microwave or in a bowl over a pan of simmering water. Leave to cool for a few minutes
  • Using an electric whisk/stand mixer, whisk your eggs and sugar together for 5 minutes or so on high speed, or until the mixture has doubled in volume, is alot paler, and leaves a trail for a few seconds when you lift the whisk out.
  • Pour in the chocolate/butter mix and fold through very carefully.
  • Add in the flour and cocoa powder and fold through carefully again.
  • Add in your frozen chunks of Mars Bar and chocolate chips and fold in. Pour the mixture into the tin and bake in the oven for 25-30+ minutes.
  • Leave to cool in the tin, and then enjoy!
  • To decorate your brownies if you fancy it... melt your chocolate and drizzle over the brownies, and add pieces of Mars Bar to each one! Set in the fridge, then chop up and enjoy!

Notes

  • Please try and freeze the Mars Bar first as it'll work so much better!
  • These will last for one week+!
  • You can use caster sugar instead of the brown sugar, the brown sugar just works really well for the Mars Bar theme!
  • If your brownies are taking much longer than stated to bake, your oven may have been the wrong temperature, or you over mixed your batter. Keep adding on 5 minutes till they're done and cover with foil if need be!

ENJOY!

Find my other Recipes on my Recipes Page!

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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.

243 Comments

  1. Bethany on March 28, 2021 at 6:16 pm

    5 stars
    Love this recipe so much made these the other day and super yummy. I was wandering if I wanted to add Lindt balls instead of Mars bar would I need to freeze them? And do I need to chop them in half as well or leave them whole? Thank you so much.

  2. Caroline Littleboy on March 23, 2021 at 8:26 pm

    Hi Jane, PLEASE can you help me.
    My Goddaughter has asked me to make Reese Brownies for her boyfriend….. I always make your Mars Bar brownies and thought maybe I could tweak this recipe by swapping the Mars bars for the Reese little cupcakes and maybe adding a little bit of peanut butter… Any advice please?? X
    P. S I’ve pre-ordered your book and I’m super excited for August!!!!

    • Jane's Patisserie on March 26, 2021 at 1:46 pm

      Hello! Yes that sounds great. You can basically merge my biscoff and mars bar recipes – maybe add up to 200g peanut butter. Ahh thank you so much for pre-ordering the book, I am so so excited too!xx



  3. Kelly Jennings on March 10, 2021 at 7:57 pm

    5 stars
    Hi Jane
    Can you use double decker in these and do you have to freeze them.

    • Jane's Patisserie on March 10, 2021 at 8:05 pm

      yes you can, and yes I would freeze them!



    • Sara Young on November 7, 2021 at 12:31 pm

      I’ve made this recipe a couple of times and they are the
      best brownies. Everyone loves them!



  4. Amy on March 8, 2021 at 6:27 pm

    Hi Jane.
    My brownie top cracks when baking, why is this? X

    • Jane's Patisserie on March 8, 2021 at 7:34 pm

      Do you mean there are actual cracks or like the top has a fine layer that cracks a bit? x



  5. Laura on March 6, 2021 at 8:29 pm

    5 stars
    Hi Jane. Thank you for your recipes, they’re amazing! I’ve made lots of your bakes and they’re a hit with family and friends. I don’t suppose you could help me with adapting the recipe could you please? I want to make a large traybake and a small traybake for a family birthday but I’m not sure of quantities. The tray sizes are 32cmx20cm (12.5”x8”) and 19cmx13cm (7.5”x5”).
    THANK YOU!

  6. Sophie on March 5, 2021 at 6:58 pm

    4 stars
    Really good! But they have come out a bit rich. Could anyone help me make them less bitter/rich? 🙂

    • Jane's Patisserie on March 6, 2021 at 7:05 pm

      What chocolate did you use? They are rich however so it may be best just to eat a smaller slice!!



  7. grace Kumar on March 5, 2021 at 1:19 pm

    5 stars
    this si sooo good this si the 9 th time i have made them for a party

  8. Tamsin on March 4, 2021 at 11:21 pm

    I made these last week and they are the best brownies I have ever made!!!!!! Can these be done with Reese’s peanut butter cups too? Would I have to freeze them? Thanks so much x

    • Jane's Patisserie on March 6, 2021 at 7:09 pm

      AHh yay!! And yeah I would freeze them just in case x



  9. Keri on March 4, 2021 at 1:32 pm

    5 stars
    I use all these recipes for all of my baking and wow they’re incredible every time! However, I struggle to cut the brownies to look neat- they always seem to break (the top only) as I cut and I can never get clean lines… any suggestions to help with this please?? 🙂

    • Jane's Patisserie on March 4, 2021 at 10:41 pm

      Honestly all I use is one large sharp knife and cut down across the width of the tray!



  10. Beth on February 26, 2021 at 6:08 pm

    How do I know when these are cooked? I had them in for 35 minutes (with foil on for the last 5) but the knife still comes out wet when I test it. I want the brownies kinda gooey so is there a tell sign to know when up the bake is just right? I’m worried they’ll turn out cakey if I cook them any longer!

    • Jane's Patisserie on March 3, 2021 at 9:13 pm

      I look for an ever so slight wobble in the tin, then let them cool fully in the tin!



  11. Jess on February 24, 2021 at 4:49 pm

    5 stars
    I’ve made these a few times and amazing recipe but this time they’ve come out more cake like and without the brownie ‘crust’ on top. What have I done wrong?

  12. Grace on February 18, 2021 at 11:47 am

    Hi,
    Is there any way to reduce the amount of chocolate in these or have you ever reduced it and found it to work? They just have soo much chocolate in.🍫😂

    • Jane's Patisserie on February 18, 2021 at 8:22 pm

      You can’t reduce the base brownie mixture – but you can easily add less chunks!



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