Preheat your oven to 190ºC/170ºCfan and line a 9x9inch square tin with parchment paper, and leave to the side for now.
Whisk/mix the plain flour, bicarbonate of soda, salt and cornflour together so its evenly distributed – leave to the side.
In a larger bowl, melt the unsalted butter/stork. Add in both the granulated sugar and light brown sugar, and whisk for about 2 minutes so all of the sugar starts to dissolve and the mixture is smooth.
Add in the egg and the vanilla bean extract, and whisk again briefly until smooth. (I used an electric whisk)
Add in the dry ingredients, the Rolos (apart from a handful), and the milk chocolate chips. Mix with a spatula until a thick cookie dough is formed.
Press the mixture into the bottom of the tin and press in the handful of Rolos into the top for decoration.
Bake the traybake in the oven for 18-22 minutes, until the top of the cookie bake looks ‘dry’!
Leave the cookie bake to cool for about 10 minutes, then leave to cool fully on a wire rack.
Cut the bake when it’s cooled into 4×4 for decent sizes, or 5×5 for smaller ones! Enjoy!
Notes
For these babies, feel free to use big Rolos, mini Rolos, a mixture - whatever you fancy!
If you can’t access Rolos, you could use something that is a soft caramel like pieces of Cadbury’s caramel maybe? I wouldn’t suggest using a hard caramel sweet however as it will bake differently. You could also use something such as Munchies!
These delicious little things will last in an airtight container for up to 5 days, but honestly, they’ll be eaten before then.
You can freeze these once baked for up to 3 months, or from unbaked for 3 months also. If baking from frozen, just add on 2-3 minutes extra!