Ok, let’s start by addressing the name of this recipe! I didn’t invent the term “slutty brownies” however it has become an increasingly common way to refer to what were previously know as brookies. Brookies are a type of traybake made up of a layer of cookie dough, a layer of Oreos and then brownie mix on top. As soon as I saw the new Biscoff sandwich biscuits, I knew I wanted to make Biscoff Slutty Brownies with them!
Let’s go through the layers. First we have a cookie dough layer dotted with both milk and white chocolate chips. Then in the middle are Biscoff sandwich biscuits – two circular speculoos biscuits with a biscoff creme in the centre. On top are rich chocolate brownies swirled with Biscoff spread. They are incredibly indulgent and SO delicious!!
How to make Biscoff Slutty Brownies…
I started by making the cookie dough layer. I mixed butter and light brown sugar together, then add milk and vanilla extract. Then I mixed in plain flour, salt and chocolate chips. I pressed it into the bottom of my tin.
For the brownie layer, I melted butter and dark chocolate together in a pan on a low heat. In a mixing bowl I whisked together light brown sugar, vanilla extract and eggs. Then I poured the chocolate mixture into the egg mixture and whisked to combine.
Finally I stirred in plain flour, cocoa powder and chocolate chips. Before adding it to the tin, I first placed the Biscoff sandwich biscuits all over the top of the cookie dough.
I added the brownie mixture on top and then spoonfuls of Biscoff spread. I used a knife to swirl the Biscoff spread around, then put it in the oven to bake.

What if you can’t find Biscoff sandwich biscuits?
You can use regular Lotus Biscoff biscuits instead for the biscuit layer. I got the sandwich biscuits from Tesco, and Sainsburys sell them too. You can also order them online from Amazon.
Why are they called Slutty Brownies?
I have to say I am not a huge fan of the name, I much prefer the terms brookies or ultimate cookie dough brownies (both better names if you’re making them with your kids!) But the internet has grasped onto the term and it’s now the most well known way to refer to this combination.
From my research, the concept of Slutty Brownies emerged online in May 2011. Both KevinAndAmanda.com and The Londoner are credited with being the first to post recipes. Their recipes both use box mixes, which I personally cannot endorse as I am very much a make it from scratch girl! However, myself (along with thousands of others I’m sure) will always be grateful for them for introducing this recipe concept to the world!

Tips for making the Biscoff Slutty Brownies:
- If you don’t have, or can’t get hold of light brown sugar, you can use caster sugar for the cookie and brownie layers instead.
- I used a mixture of white and milk chocolate chips for the cookies, and dark chocolate chips for the brownies. You can mix this up any way you prefer. Use white chocolate chips only for example, or dark chocolate in the cookies and white and milk in the brownies – whatever you fancy!
- The brownies can be frozen. Wrap them well and freeze for up to 3 months.

Recommended equipment & ingredients*
8″ Square tin | Mixing bowls | Cooling rack |
Kitchen scales | Stand mixer | Biscoff spread |
Dark chocolate | Biscoff Sandwich Biscuits |
*I earn a small amount of money if you buy the products after clicking on the links. You will not be charged anything extra for this. Thank you for supporting The Baking Explorer!

More Biscoff recipes…

Biscoff Slutty Brownies
Ingredients
For the cookie dough layer
- 120 g Butter softened
- 150 g Light brown sugar
- 25 ml Milk
- 1 tsp Vanilla extract
- 185 g Plain flour
- 1/4 tsp Salt
- 50 g White chocolate chips
- 50 g Milk chocolate chips
For the biscuit layer
- 20 Lotus sandwich biscuits
For the brownie layer
- 235 g Dark chocolate
- 165 g Butter
- 165 g Light brown sugar
- 2 Eggs large
- 1 tsp Vanilla extract
- 65 g Plain flour
- 20 g Cocoa powder
- 50 g Dark chocolate chips
- 100 g Biscoff spread
Instructions
- Pre-heat your oven to 160C Fan/180C/350F/Gas Mark 4, line a 8" square tin with greaseproof paper. I grease the tin first with a little butter to help the paper stick to it
- To make the cookie dough base, using a stand mixer with the paddle attachement, or by hand with a spoon, mix the butter and sugar together until fluffy and well combined
- Add the milk and vanilla extract and mix well until combined
- Then add the plain flour and salt, and mix until a dough forms
- Finally mix in the chocolate chips until well distributed
- Press the cookie dough into the bottom of the tin using your hands, try and make it an even layer
- Put the cookie dough in the fridge while you make the brownies, or for at least 30 minutes
- To make the brownie batter, melt the dark chocolate and butter together in a pan on a low heat. When fully melted, stir together and remove from the heat. Let it cool for 10 minutes
- In a mixing bowl whisk together the eggs and light brown sugar until frothy, by hand with a whisk or with an electric whisk
- Add the melted chocolate and butter mixture to the egg and sugar mixture, whisking constantly as you pour it in
- Add the plain flour and cocoa powder, and whisk in gently
- Then stir in the chocolate chips
- Take the tin with the cookie dough in it out of the fridge and cover them with the Biscoff sandwich biscuits, you may need to chop some of the biscuits in half to fully cover the cookie dough
- Pour the brownie batter over the top, then add spoonfuls of the Biscoff spread all over. Use a butter knife to swirl it around a little bit – don't over mix
- Bake for 45-55 minutes, the brownie layer should not wobble (or only very slightly) when you gentle shake the tin
- Let the brownies cool completely in the tin before removing and slicing up
- Store in an airtight container in a cool place and eat within 3 days, they can also be frozen
Video
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NB. this post is NOT sponsored by Lotus Biscoff – I just love their products!
If you like this, check out more of my Brownie recipes!

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I’m linking this recipe up with Cook Blog Share hosted by Glutarama.
These sound totally delicious and I’m sure it’s impossible to eat just one piece! I’d need to freeze most of mine to keep me from eating the whole tray.
OMG those look amazing! Although I think a pretty small piece would probably be enough!
Thank you! Yes I did them in smaller portions than my standard brownies as they are very indulgent 🙂
They sounds like a fantastic combination of flavours and textures and I know my family would absolutely love them – I’d probably be lucky if I managed to eat any!
Another Fab recipe & great flavours! Nothing makes me sadder than Biscoff being full of soya as its such a lovely flavour to use in baking!
Sweet jesus, you’ve combined all of my great loves into one bake. I’m in love 😍
I rarely envy others for their baking but you my lovely I ALWAYS envy hahaha, these sound delicious. I reckon I could make these GF for Bethany with the Festive Specculas Biscuits from Schar at the moment, they’re so similar to Biscoff biscuits. Will have to give it a go.
Aww thank you Rebecca, that’s so sweet! Oh yes I definitely think they could be made GF – if anyone can do it, you can!
These look truly amazing (although I have to agree about the name, i prefer the name brookies too!)
These look incredible! Like you I’m not the biggest fan of the name but I’m sure after one bite of these bad boys it doesn’t matter what they’re called! Amazing.
Hi
Will the cookie get over cooked?
Hi, no it won’t, make sure you chill it for at least 30 minutes as per the recipe instructions 🙂