Preheat oven to 350°F and line an 8-inch baking pan with parchment paper and spray the sides of the pan with non-stick cooking spray.
Peanut Butter Layer
Combine peanut butter, melted butter, sugar, brown sugar, egg, and vanilla in a large bowl.
In a small bowl, combine flour, baking powder, and salt. Add the dry ingredients to the peanut butter mixture. Spread the peanut butter layer on the bottom of the prepared pan.
Chocolate Layer
Combine flour, cocoa powder, and salt in a medium bowl.
In a separate bowl, whisk together the melted butter, sugar, eggs, and vanilla.
Lightly fold the flour mixture into the wet ingredients. Do not mix or the brownies will turn out cake-like.
Top the peanut butter layer with the brownie batter, spreading the batters for both layers out evenly.
Baking Time
Bake for 22 minutes. Brownies will still be soft and gooey, but will finish setting while they cool.
Video
Notes
Measurements: Accurate measurements of ingredients like flour, cocoa, and sugar ensure consistent and delicious brownies.
Mixing: Gently mix wet and dry ingredients until just combined to avoid overmixing, which can lead to dense brownies.
Quality Cocoa: Use high-quality cocoa powder for rich flavor. Dutch-processed cocoa can enhance the depth of chocolate taste.
Doneness Test: Insert a toothpick into the center – it should come out with a few moist crumbs for fudgy brownies or clean for cake-like ones.
Cooling Time: Allow brownies to cool in the pan for a bit before transferring to a wire rack. This helps them set and become easier to cut.