Decadent Peanut Butter-Stuffed Brownies Recipe

Thick, fudgy and utterly decadent – these peanut butter stuffed brownies have a creamy peanut butter filling sandwiched between layers of chocolate brownie. The perfect treat if you love the peanut butter and chocolate combination.

I have many brownie recipes and several peanut butter variations—peanut butter cheesecake brownies, peanut butter frosted brownies, and brownies with peanut butter mixed into the batter. But you can never have too much of that salty-sweet peanut butter with a gooey, fudgy brownie.

These peanut butter stuffed brownies deliver an extra-thick, chewy chocolate base with a dense peanut butter center that tastes like a peanut butter cup. They bake up with shiny tops and a perfect texture, but it’s the flavor pairing of peanut butter and chocolate that really makes them special.

Making Peanut Butter Stuffed Brownies

When I first tested this recipe I used plain peanut butter for the filling, but it was too runny and oozed out after baking. The trick is to thicken the filling so it holds its shape. This filling is similar to the center of a peanut butter cup: combine 3/4 cup smooth peanut butter with 1 cup powdered sugar and 1 teaspoon vanilla extract. The result should be much thicker than regular peanut butter. Chill the mixture while you prepare the brownie batter.

The brownie batter is designed to be thick and chewy, made with both melted chocolate and cocoa powder for a deep chocolate flavor.

1. Whisk together the dry ingredients—flour, cocoa and salt—to remove lumps and help them incorporate evenly. Dutch-process (specialty dark) cocoa gives the best flavor, but regular cocoa works too.
2. Melt the butter and chocolate together slowly, either in the microwave at medium power in 45-second intervals, stirring between each, or over a double boiler with gently simmering water. Avoid overheating to prevent grainy or burned chocolate.
3. Let the chocolate mixture cool for a few minutes, then whisk in the sugar, two whole eggs, one additional egg yolk (for extra chewiness) and the vanilla extract until glossy and combined.
4. Sift or whisk the dry ingredients into the chocolate mixture and gently mix until smooth and no streaks remain. The batter should be shiny and slightly thick.

Assemble the brownies as follows:

1. Pour half of the brownie batter into a prepared 8×8 inch (20×20 cm) pan lined with parchment paper and smooth it into an even layer.
2. Remove the peanut butter filling from the fridge, scoop tablespoon-sized portions, flatten into discs and arrange them in an even layer on top of the brownie base. Lightly greasing your fingers first makes this step easier.
3. Drop spoonfuls of the remaining brownie batter over the peanut butter pieces, then spread gently into an even top layer to fully cover the filling. Avoid pouring the batter directly in one spot, which can disturb the peanut butter layer.

Bake in a preheated oven at 350°F (180°C) for about 30–35 minutes, depending on how gooey you like them and your oven’s behavior. The top should look set and a toothpick inserted into the center should come out clean or with a few damp crumbs; it should not have runny batter. Let the brownies cool completely in the pan so the peanut butter center firms up and doesn’t ooze when sliced. Chilling the pan briefly in the refrigerator can speed this up and help produce clean slices.

Thick, fudgy and the ideal balance of peanut butter and chocolate—these brownies deliver. If you enjoy this flavor pairing, try other chocolate-and-peanut-butter recipes for variety.

Equipment

• 8×8 inch (20×20 cm) pan

Ingredients

Peanut Butter Filling

• 3/4 cup smooth peanut butter (not natural)
• 1 cup powdered sugar (110 grams), sift if lumpy
• 1 teaspoon vanilla extract

Brownie Batter

• 1/2 cup all-purpose flour (63 grams)
• 1/4 cup cocoa powder (22 grams)
• 1/4 teaspoon salt
• 1/2 cup unsalted butter (112 grams)
• 6 ounces semi-sweet chocolate (about 180 grams) (50–60% dark recommended)
• 1 cup granulated sugar (200 grams)
• 2 large eggs
• 1 large egg yolk (discard white)
• 1 teaspoon vanilla extract

Instructions

1. Preheat the oven to 350°F (180°C). Line an 8×8 inch pan with parchment paper, leaving an overhang to lift the brownies out later. Lightly grease the pan first so the parchment adheres.
2. For the peanut butter filling: In a medium bowl, beat together the peanut butter, powdered sugar and vanilla until combined. Chill while preparing the batter.
3. For the brownie batter: Whisk the flour, cocoa and salt in a small bowl and set aside. Melt the butter and chocolate together slowly, either in 45-second microwave intervals on medium power or over a double boiler. Let cool about 5 minutes.
4. Whisk the sugar, two eggs, the extra egg yolk and vanilla into the melted chocolate until glossy. Add the dry ingredients and fold or whisk until smooth with no streaks.
5. Assembly: Spread half the batter into the prepared pan. Arrange flattened scoops of the chilled peanut butter filling in an even layer. Spoon the remaining batter over the filling, gently smoothing to cover.
6. Bake in the center of the preheated oven for about 32–37 minutes, or until the top is set and a toothpick comes out clean or with a few moist crumbs. Avoid overbaking to keep the brownies fudgy.
7. Cool the brownies in the pan until the pan is no longer warm—this can take a few hours. To speed cooling, place the pan on a wire rack in the fridge. When fully cooled, lift the brownies out using the parchment overhang and slice with a sharp knife.

Notes

1. Peanut Butter: Use smooth, commercially prepared peanut butter (not natural varieties where oil separates).
2. Salted Butter: If you use salted butter, you can omit the added salt.
3. Chocolate: Chocolate chips or chopped chocolate bars both work. Semi-sweet or 50–60% dark chocolate pairs best with the peanut butter; higher percentages may be too intense for this recipe.
4. Storage: Store in an airtight container at room temperature for up to 4 days. Freeze tightly wrapped for up to 3 months; thaw in the fridge.
5. Nutrition: Nutrition values are estimates per brownie when the pan is cut into 12 pieces.