Gluten-Free Slutty Brownies
These Gluten-Free Slutty Brownies layer cookie dough, Oreos, and fudgy brownie into irresistible cookie brownie bars. Easy, decadent, and totally foolproof!
Well… let me tell you about the time I brought these gluten-free slutty brownies to a Fourth of July cookout, fully expecting them to sit quietly on the dessert table next to the flag cake. They were gone in twelve minutes. Twelve. Someone actually asked me if I owned a bakery, and honestly? That might’ve been the proudest moment of my entire kitchen career.
Here’s the thing — going gluten-free doesn’t mean you surrender the outrageously indulgent stuff. These layered brownies are living, chocolatey proof of that. Three layers of pure bliss stacked into one pan: a buttery cookie base, a middle of gluten-free Oreos, and a rich, fudgy brownie blanket draped right on top.
Whether you’re new to gluten-free baking or you’ve been at it for years, these cookie brownie bars are the kind of recipe that makes everyone at the table forget they’re gluten-free. And isn’t that exactly the point? They’re simple enough for a weeknight treat and impressive enough for any gathering you want to absolutely win.
Why These Gluten-Free Slutty Brownies Actually Work
If you’ve ever had a gluten-free bake turn out dry, crumbly, or just kind of sad, I get it. The secret with these oreo brownies is the structure of the layers — each one protects the others during baking, keeping everything moist and fudgy.
The cookie base holds its own thanks to a combination of gluten-free flour, xanthan gum, and cornflour working together. According to the Celiac Disease Foundation’s guide to gluten-free baking, xanthan gum acts as a binder that mimics the elasticity gluten normally provides. That little quarter teaspoon makes a world of difference here.
The brownie top stays dense and gooey because of the melted chocolate-butter combo folded gently into whipped eggs. It bakes into something as rich and velvety as a truffle, with edges that get just slightly crisp. These gluten-free slutty brownies genuinely rival any wheat-flour version out there.
Table of Contents
Ingredients for Gluten-Free Slutty Brownies
Cookie Bar Base
| Ingredient | Amount | Notes |
|---|---|---|
| Butter, melted | 130 g | Or dairy-free alternative |
| Caster sugar | 50 g | |
| Light brown sugar | 150 g | |
| Large egg | 1 | Egg replacer if necessary |
| Vanilla extract | 1 tsp | |
| Gluten-free plain flour | 280 g | |
| Xanthan gum | ¼ tsp | |
| Bicarbonate of soda | 1 tsp | |
| Cornflour (corn starch) | 1 tbsp | |
| Chocolate chips | 150 g | Dairy-free if necessary |
Oreo Centre
| Ingredient | Amount | Notes |
|---|---|---|
| Gluten-free Oreos | 1–2 packs | Enough to cover the cookie base |
Brownie Top
| Ingredient | Amount | Notes |
|---|---|---|
| Gluten-free plain flour | 50 g | |
| Cocoa powder | 25 g | Ensure dairy-free if needed |
| Butter | 125 g | Or dairy-free alternative |
| Chocolate | 125 g | Half dark, half milk (dairy-free if necessary) |
| Medium eggs | 2 | Egg replacer if necessary |
| Caster sugar | 140 g | |
| Chocolate chips (optional) | 60 g | Dairy-free if necessary |
Instructions: How to Make Gluten-Free Slutty Brownies
Step 1 — Prep Your Pan
Line a 9×9 inch square baking tin with non-stick baking paper, letting a little hang over the sides for easy lifting later. Preheat your oven to 160°C Fan / 180°C conventional.
Step 2 — Mix the Cookie Base Sugars and Butter
Add your melted butter, caster sugar, and light brown sugar to a large bowl. Stir with a spatula until everything is completely combined — this takes a couple of minutes by hand. Let the mixture sit for a moment so it thickens up slightly.
Step 3 — Add Egg and Vanilla
Drop in your egg and vanilla extract. Mix again until the batter looks smooth and glossy, with no streaks of egg visible.
Step 4 — Build the Cookie Dough
Add your gluten-free plain flour, xanthan gum, bicarbonate of soda, salt, and cornflour to the bowl. Stir by hand — it’ll feel like it’s never going to come together, but keep at it. You’ll end up with a thick, scoopable cookie dough that smells absolutely heavenly.
Step 5 — Fold in Chocolate Chips
Scatter your chocolate chips into the dough and fold them through evenly. Every bite of these cookie brownie bars deserves a pocket of melty chocolate.
Step 6 — Press into the Pan
Spoon the cookie dough into your prepared tin. Push it to the edges with your fingertips, making sure the layer is even and gap-free. Get your hands right in there if you need to — no judgment in this kitchen.
Step 7 — Freeze the Cookie Base
Pop the tin into the freezer for at least 15 minutes. This firms up the dough so it stays distinct from the brownie layer. Use this time to make your brownie batter.
Step 8 — Melt Chocolate and Butter for the Brownie
Melt your butter and chocolate together in the microwave (in short bursts, stirring between) or over a bain-marie. Stir until silky and smooth, then set aside to cool to just barely warm — you should be able to comfortably touch the bottom of the bowl.
Step 9 — Sieve the Dry Ingredients
Sieve your cocoa powder and gluten-free flour into a separate bowl. Give it a quick whisk to combine, then set it aside. This step prevents lumps and keeps those layered brownies smooth.
Step 10 — Whip Eggs and Sugar
In another bowl, crack your eggs and add the caster sugar. Beat with an electric hand whisk until the mixture turns paler and looks slightly frothy — almost like a light mousse. This gives the brownie its beautiful lift.
Step 11 — Combine Chocolate with Eggs
Pour the cooled chocolate-butter mixture into the egg and sugar bowl. Fold gently with a spatula — watch it marble into gorgeous swirls before becoming one deep, chocolatey river. The aroma at this stage is absolutely intoxicating.
Step 12 — Fold in the Dry Mix
Add your sieved flour and cocoa powder mixture to the brownie batter. Fold until just combined — no white streaks, but don’t overwork it. Fold in your optional chocolate chips for extra pockets of melt.
Step 13 — Assemble the Layers
Pull your cookie base from the freezer. Arrange gluten-free Oreos across the entire surface, breaking some into pieces to fill gaps. This is the layer that makes these oreo brownies truly legendary.
Step 14 — Add the Brownie Batter
Pour or spoon the brownie batter over the Oreo layer. Spread gently with a spatula until even. Sprinkle extra chocolate chips on top — because more chocolate is always the right answer.
Step 15 — Bake
Slide the tin into the oven and bake for 35–40 minutes. The top should look set with a slight wobble in the centre — that’s how you know the inside stays fudgy. Let the gluten-free slutty brownies cool completely in the tin before slicing into squares.
Substitutions for Gluten-Free Slutty Brownies
Dairy-Free: Swap butter for a quality dairy-free baking block (I love the ones that come in foil-wrapped sticks for easy measuring). Use dairy-free chocolate and dairy-free chocolate chips throughout. These layered brownies turn out just as indulgent without a drop of dairy.
Egg-Free: A flax egg (1 tbsp ground flaxseed + 3 tbsp water, rested 5 minutes) works well in the cookie base. For the brownie layer, try a commercial egg replacer designed for binding — two flax eggs can make the brownie a bit dense. Test with one batch first.
Sugar Swaps: Coconut sugar works beautifully in place of both the caster and light brown sugar. The cookie brownie bars will be slightly darker in colour with a deeper caramel undertone, which honestly tastes wonderful.
Oreo Alternatives: If you can’t find gluten-free Oreos in your area, any gluten-free chocolate sandwich cookie will do the job. You could also use gluten-free digestive biscuits spread with a thin layer of chocolate hazelnut spread for a different spin on these oreo brownies.
Flour Brands: Not all gluten-free flours behave the same way. If your blend doesn’t already contain xanthan gum, keep the ¼ tsp called for here. If it does, you can skip the extra xanthan — just check the packet. For more on navigating flour differences, our beginner-friendly gluten-free baking tips can help you feel more confident.
Troubleshooting Your Gluten-Free Slutty Brownies
The brownie layer is raw in the middle. This usually means the oven ran a bit cool or the batter was spread too thickly. Try baking for an additional 5–8 minutes with a sheet of foil loosely tented on top to protect the surface from over-browning.
The cookie base crumbled apart when I cut them. Next time, make sure the cookie dough is firmly packed into the tin with no air pockets. Freezing for a full 15 minutes (not less) also helps the base hold its shape beneath those layers.
My brownie top cracked. You know… a crackly top on these layered brownies is actually a sign of a well-whipped egg and sugar mixture, so it’s not a flaw — it’s a feature. If you prefer a smoother top, fold the chocolate into the eggs more gently and whip a bit less.
The Oreos got soggy. A little softness is expected and delicious, but if they turned to mush, the brownie batter may have been too warm when poured. Let the batter cool to room temperature before assembling so the cookies hold their texture in these gluten-free slutty brownies.
Everything stuck to the pan. Line the tin with enough baking paper to create handles on two sides. Once cooled, lift the whole slab out in one piece, then slice on a cutting board. This also makes for much cleaner cookie brownie bars.
How to Store Gluten-Free Slutty Brownies
These gluten-free slutty brownies keep beautifully at room temperature in an airtight container for up to 3 days. The layers actually meld together and taste even better on day two — the cookie gets chewier and the brownie becomes denser and more fudge-like.
For longer storage, pop them in the fridge for up to a week. Let them come to room temperature for about 20 minutes before serving, or enjoy them cold if you like a firmer, truffle-like bite.
Meal Prep & Freezing
These layered brownies are freezer superstars. Wrap individual squares in cling film, then store in a freezer bag for up to 3 months. They thaw at room temperature in about an hour — or for 15 seconds in the microwave if patience isn’t your thing that day. They’re perfect for packing into lunchboxes or stashing away for a guaranteed emergency dessert.
Serving Suggestions & Pairings
Serve a warm square of these gluten-free slutty brownies with a generous scoop of vanilla ice cream and watch it melt into all the crevices. A drizzle of salted caramel sauce takes the whole experience over the top.
For a lighter pairing, a cold glass of oat milk or a hot cup of strong coffee cuts through the richness perfectly. These cookie brownie bars also pair surprisingly well with fresh raspberries — the tartness is a gorgeous contrast to all that chocolate.
If you’re serving them at a party or potluck, slice them small. They’re incredibly rich, so bite-sized pieces on a pretty platter go a long way. Stack them in a little tower for a dessert table that looks like it came straight off Pinterest.
Need a full menu? These oreo brownies pair wonderfully after a savoury main like our comforting gluten-free tamale pie or a light dinner like our flavour-packed crustless quiche.
Variations & Dietary Adjustments
Kid-Friendly Version: Man, oh man… kids go absolutely wild for these. Let them help press the cookie dough and arrange the Oreos — it’s the kind of hands-on baking that makes memories. For younger ones, skip the dark chocolate in the brownie and use all milk chocolate for a sweeter, milder flavour.
Peanut Butter Swirl: Warm 3 tablespoons of peanut butter until drizzleable, then swirl it over the brownie batter before baking. The nutty richness against the chocolate layers is genuinely incredible. Use sunflower seed butter for a nut-free alternative to keep these gluten-free slutty brownies allergy-friendly.
White Chocolate & Raspberry: Replace the brownie’s chocolate chips with white chocolate chips and press a handful of fresh raspberries into the Oreo layer before adding the batter. The result is a fruity, tangy twist on classic layered brownies that looks stunning when sliced.
Extra Fudgy / Underbaked Centre: If you love a brownie that’s practically molten, pull the pan at 32 minutes and let it cool completely in the tin. The residual heat finishes the cook while keeping the centre impossibly gooey. These oreo brownies become almost like a layered chocolate truffle bar.
FAQs About Gluten-Free Slutty Brownies
Can I make gluten-free slutty brownies ahead of time?
Absolutely — they actually improve with a day of rest. Bake them the day before, store in an airtight container, and slice when you’re ready to serve. The flavours deepen and the layers set up perfectly.
How do I know when layered brownies are done baking?
Look for a set top with a gentle wobble in the centre when you tap the side of the tin. A toothpick inserted should come out with moist crumbs, not wet batter. Overbaking is the number one enemy of fudgy cookie brownie bars.
What’s the best way to cut clean squares?
Let the brownies cool completely — rushing this step is tempting but leads to messy slices. Use a sharp knife dipped in hot water and wiped clean between each cut. Lifting the slab out using the baking paper handles also makes a huge difference.
Why are they called “slutty” brownies?
The name comes from the gloriously over-the-top, no-holds-barred layering of three separate desserts into one pan. It’s meant to be playful and fun — these gluten-free slutty brownies are unapologetically indulgent, and that’s the whole point.
Can I use a different size baking tin for these oreo brownies?
A 9×9 inch tin gives you the ideal thickness for all three layers. If you use a larger pan, the layers will be thinner and you’ll need to reduce baking time by about 5–8 minutes. A smaller tin means thicker layers and a longer bake.
How do I make these cookie brownie bars completely vegan?
Use dairy-free butter, dairy-free chocolate, and egg replacers in both the cookie and brownie layers. Flax eggs work in the cookie base, and a combination of flax egg plus a tablespoon of aquafaba gives the brownie layer better structure.
Gluten-Free Slutty Brownies
Equipment
- 9×9 inch square baking tin
- non-stick baking paper
- Large mixing bowls
- Spatula
- electric hand whisk
- Sieve
- microwave or bain-marie
Ingredients
For the Cookie Bar Base
- 130 g butter melted, or dairy-free alternative
- 50 g caster sugar
- 150 g light brown sugar
- 1 large egg egg replacer if necessary
- 1 tsp vanilla extract
- 280 g gluten-free plain flour
- ¼ tsp xanthan gum
- 1 tsp bicarbonate of soda
- 1 tbsp cornflour also known as corn starch
- 150 g chocolate chips dairy-free if necessary
For the Centre
- 1-2 packs gluten-free Oreos
For the Brownie Top
- 50 g gluten-free plain flour
- 25 g cocoa powder ensure dairy-free if needed
- 125 g butter or dairy-free alternative
- 125 g chocolate half dark and half milk, dairy-free if necessary
- 2 medium eggs egg replacer if necessary
- 140 g caster sugar
- 60 g chocolate chips optional, dairy-free if necessary
Instructions
- Line a 9×9 inch square baking tin with non-stick baking paper, letting a little hang over the sides for easy lifting later. Preheat your oven to 160°C Fan / 180°C conventional.
- Add your melted butter, caster sugar, and light brown sugar to a large bowl. Stir with a spatula until everything is completely combined — this takes a couple of minutes by hand. Let the mixture sit for a moment so it thickens up slightly.
- Drop in your egg and vanilla extract. Mix again until the batter looks smooth and glossy, with no streaks of egg visible.
- Add your gluten-free plain flour, xanthan gum, bicarbonate of soda, salt, and cornflour to the bowl. Stir by hand — it’ll feel like it’s never going to come together, but keep at it. You’ll end up with a thick, scoopable cookie dough that smells absolutely heavenly.
- Scatter your chocolate chips into the dough and fold them through evenly.
- Spoon the cookie dough into your prepared tin. Push it to the edges with your fingertips, making sure the layer is even and gap-free. Get your hands right in there if you need to.
- Pop the tin into the freezer for at least 15 minutes. This firms up the dough so it stays distinct from the brownie layer. Use this time to make your brownie batter.
- Melt your butter and chocolate together in the microwave (in short bursts, stirring between) or over a bain-marie. Stir until silky and smooth, then set aside to cool to just barely warm.
- Sieve your cocoa powder and gluten-free flour into a separate bowl. Give it a quick whisk to combine, then set it aside.
- In another bowl, crack your eggs and add the caster sugar. Beat with an electric hand whisk until the mixture turns paler and looks slightly frothy.
- Pour the cooled chocolate-butter mixture into the egg and sugar bowl. Fold gently with a spatula — watch it marble into gorgeous swirls before becoming one deep, chocolatey river.
- Add your sieved flour and cocoa powder mixture to the brownie batter. Fold until just combined with no white streaks, but don’t overwork it. Fold in your optional chocolate chips for extra pockets of melt.
- Remove your cookie base from the freezer. Arrange gluten-free Oreos across the entire surface, breaking some into pieces to fill gaps.
- Pour or spoon the brownie batter over the Oreo layer. Spread gently with a spatula until even. Sprinkle extra chocolate chips on top.
- Place in the oven and bake for 35–40 minutes. The top should look set with a slight wobble in the centre. Allow to cool completely in the tin before cutting into squares and enjoying!
