Cookies ‘n’ Creme Slice

Gotta tell you guys, I’m surprised this traybake worked! I made this to take back up to Scotland for my sisters birthday. I always bake something for peoples birthdays! I wanted to make something with Oreos and I thought about a Rocky Road. Now, don’t get me wrong, I love a Rocky Road, but I find them quite firm if you know what I mean?! Like, there’s so soft squidginess to them, they’re almost a little crumbly. So I decided to go for something a little more along the lines of my Fudgy Easter Slice, by adding golden syrup and butter to the mixture. Hence why I wasn’t sure whether this would work!! White chocolate can be temperamental, especially when mixed with golden syrup and butter! It can split easier than milk or dark chocolate and I find it can burn quicker! But I was brave and it worked! I think the trick is to go slow and steady and take it off the heat for a little while if you feel it is thickening too quickly or feels like it’s going to burn. But if you’re a little apprehensive about this, then feel free to change the chocolate to milk or dark. Or take the butter and golden syrup out…though you may need to adjust the amount of other ingredients slightly!


Firstly, I made my cookie dough. You can just use chopped up actual cookies from a packet if you would like, but I thought I would try something a little bit different! This cookie dough is different from the cookie dough you make if you are baking them, because you can’t have raw egg in uncooked cookie dough! I also baked the flour, just to ensure it is rid of any potential bacteria. This step is super simple. Just weigh out your flour, then spread out evenly on a greaseproof paper-covered baking tray and bake on 170℃ for about five minutes then allow to cool! Once you’ve done this all you need to do is cream the butter and sugar in a bowl, add the vanilla, then add the flour and a handful of chocolate chips and mix! It will probably be quite crumbly so all you have to do is add in a tablespoon or two of milk! This will make it quite sticky, so you’ll want to refrigerate it for at least an hour if you can!


Next, we move onto the main content once the cookie dough is sufficiently chilled! I placed the chocolate, butter and golden syrup into a large heatproof bowl and melted this over a pan of simmering water. Keep stirring this mixture and make sure that the water in the pan does not touch the bowl otherwise you risk burning the chocolate. Make sure you keep it on low heat and allow it to melt slowly. If you feel the mixture beginning to stick to the bowl, then take it off the heat for a while, turn the temperature down then return to the heat. If you end up with a few lumps of chocolate left but don’t want to risk heating it further, that’s totally fine! Nothing wrong with a few lumps of chocolate!


You’ll want to let this cool slightly so it doesn’t completely melt the cookie dough. Roughly chop your Oreos (don’t crush them, it’s nice to see the chunks of biscuit throughout the slices!) and add them to the chocolate mixture along with the mini marshmallows and mix in. The cookie dough should have firmed up by now so take it out the fridge and make lots of little balls of dough! They don’t have to be the same size, or neat for that matter! Mix these in as well then press the mixture into a tin and refrigerate for at least three hours before cutting into squares!




Cookie Dough –

1 oz butter

1 ½ oz light soft brown sugar

2 oz plain flour

1 tsp vanilla

Handful of chocolate chips/chopped chocolate


Oreo Slice –

2 oz butter

9 oz white chocolate

1 tbsp golden syrup

2 packs Oreos, roughly chopped

5 oz mini marshmallows




1) Line a 9×9 baking tray with greaseproof paper and set aside. Preheat oven to 170℃.

2) Make Cookie Dough: Spread flour evenly on a sheet of greaseproof paper on a baking tray, and bake in preheated oven for about 5 minutes. Switch cooker off. In a bowl, cream together the butter and sugar then add the vanilla. Add the flour and chocolate chips and combine. Add 1-2 tbsp milk if the dough is crumbly. Allow to chill in the fridge for at least one hour.

3) Make Oreo Slice: Place butter, chocolate and golden syrup in a large heatproof mixing bowl and melt over a pan of simmering water (see notes above for more details). Remove from heat and mix in roughly chopped Oreos and mini marshmallows (save a few of each for decorating the top). Remove cookie dough from fridge and shape into balls, and add these to the mixture, and combine.

4) Press mixture into tin and allow to set in fridge for at least three hours before cutting into squares.