With a layer of chewy peanut butter cookie dough, Oreo cookies, and fudgy brownie batter on top – there’s nothing more decadent or delicious than these peanut butter slutty brownies! 
Remember the cookie dough Oreo brownies that spread across the internet a few years back? This is my twist on that trend: peanut butter slutty brownies. They keep the classic three layers — a cookie dough base, an Oreo middle, and a brownie top — but swap the chocolate chip cookie for a chewy peanut butter cookie dough. The result is gooey, peanut-butter-forward, and utterly over the top.
Peanut Butter Slutty Brownies
The peanut butter cookie layer is adapted from my peanut butter blondies recipe with a few adjustments to balance richness and structure:
- Less peanut butter so the flavor is strong without being overwhelmingly rich.
- Brown sugar for extra chewiness, used in moderation because the brownie layer adds sweetness too.
- A slightly higher flour ratio to ensure the bottom layer supports the Oreos and brownie batter.
I skipped chocolate chips in the peanut butter layer because it’s already rich, but you can stir in up to 1 1/4 cups if you want it even more decadent. Press the peanut butter cookie dough evenly across the bottom of a prepared pan, then arrange the Oreo cookies on top — I used 24 (6 rows of 4). Regular Oreos work well; peanut butter Oreos are an excellent alternative if you can find them.
The brownie batter is fudgy and chewy without being cloying. It’s made from scratch and poured over the Oreo layer so it fills the gaps around the cookies. If you prefer a boxed mix, use a mix sized for a 9×13-inch (23×33 cm) pan and follow the package instructions.
Pro tip: Bake time is around 50 minutes. I usually start checking at 45 minutes. The brownies are done when a toothpick inserted into the center comes out clean or with a few damp crumbs — slightly gooey crumbs are fine, but the toothpick shouldn’t be wet.
These slutty peanut butter brownies are:
- Peanut buttery
- Chewy
- Fudgy
- Decadently over-the-top
If you love peanut butter cookies and are ready for a serious treat, these brownies are for you.
Ingredients
Peanut Butter Layer
- 2/3 cup unsalted butter, melted
- 2/3 cup peanut butter
- 1 1/2 cups light brown sugar* (see notes)
- 1 teaspoon vanilla extract
- 2 large eggs
- 2 cups all-purpose flour
Oreo Layer
- 24 Oreo cookies
Brownie Layer
- 2/3 cup unsalted butter
- 6 oz semi-sweet chocolate, chopped (or 50–70% dark chocolate)
- 1 1/2 cups white sugar
- 3 large eggs
- 1/4 cup cocoa powder
- 3/4 cup all-purpose flour
- 1/2 teaspoon salt
Instructions
- Preheat the oven to 350°F (180°C). Line a 9×13 inch (22×33 cm) pan with parchment paper, covering the bottom and sides.
- Peanut Butter Cookie Layer:
- In a large bowl, beat together melted butter, peanut butter, and brown sugar until combined.
- Beat in the eggs and vanilla extract.
- With the mixer on low, beat in the flour until fully incorporated.
- Spread the dough evenly into the prepared pan, covering the bottom. Use lightly greased wax paper or your hands to press it smooth.
- Oreo Layer:
- Arrange 24 Oreo cookies in 6 rows of 4, pressing them gently into the peanut butter dough.
- Brownie Layer:
- Place the butter and chopped chocolate in a heatproof bowl. Microwave on medium power in 45-second intervals, stirring between each, until smooth. Alternatively, melt over a double boiler.
- Let cool briefly, then whisk in the sugar followed by the eggs.
- Gently fold in the cocoa powder, flour, and salt until just combined.
- Pour the brownie batter over the Oreo layer, making sure it fills the gaps between the cookies.
- Baking and Cooling:
- Bake for 50–55 minutes, checking at about 45 minutes. The brownies are done when a toothpick comes out with a few damp crumbs or clean; avoid a wet toothpick.
- Remove from the oven and cool in the pan for at least 4 hours, or until completely cooled.
- Lift the parchment to remove the slab from the pan, place on a cutting board, and slice into 18 large brownies.
Notes
- Light brown sugar can be substituted with 3/4 cup white sugar + 3/4 cup dark brown sugar.
- Use semi-sweet or 50–70% dark chocolate for the brownie layer. Avoid bittersweet. Chocolate chips can be used if chopped chocolate isn’t available.
- If the top browns too quickly while the center still needs time, tent with aluminum foil and continue baking.
- Store leftovers in an airtight container for up to 5 days.
Nutrition (per large brownie)
Calories: 536 kcal · Carbohydrates: 68 g · Protein: 8 g · Fat: 27 g · Saturated Fat: 13 g · Cholesterol: 95 mg · Sodium: 213 mg · Sugar: 46 g · Fiber: 3 g