Chocolate Peanut Butter Brownies combine creamy peanut butter, chopped peanuts, and chocolate chips for a rich, fudgy dessert that’s hard to resist.
If you love the classic pairing of chocolate and peanut butter, these brownies deliver both flavors in a moist, satisfying bar. The peanut butter flavor is balanced—not overpowering—and complements the deep chocolate taste for a well-rounded treat.
With only about 10 minutes of active prep time, you can whisk together the batter and have a 9″ x 13″ pan ready to bake. These brownies are delicious served either unfrosted or topped with the easy chocolate frosting included below.
Scroll down for the printable recipe card with ingredient amounts, baking times, and nutrition information.
Make the Brownie Batter
Start by measuring creamy (not natural) peanut butter, softened butter, light brown sugar, and granulated sugar into a large mixing bowl. Cream together with an electric mixer on high until fully blended. Reduce speed to medium and add vanilla and the eggs one at a time, beating well after each addition. The batter will be fairly thick at this point.
Remove the beaters and stir in unsweetened cocoa powder, all-purpose flour, semisweet chocolate chips, and finely chopped cocktail peanuts by hand until evenly distributed. The result is a thick, chocolatey peanut-butter-studded batter ready for the pan.
Bake the Brownies
Lightly grease a 9″ x 13″ baking pan and spread the batter evenly. Place the pan on the center rack of a preheated 350°F oven. Bake for 15–20 minutes, or until a toothpick inserted into the center comes out clean and the surface feels firm.
Serve Unfrosted
For unfrosted brownies, remove the pan from the oven and cut into 24 portions while still hot. Let the bars cool to room temperature in the pan before removing and serving. Unfrosted, these brownies showcase the deep chocolate and peanut butter flavors with a fudgy texture.
Frosted Option: Easy Chocolate Frosting
If you prefer frosted brownies, the simple chocolate frosting in the recipe card is quick to make while the brownies cool. To prepare, melt butter over low heat, stir in cocoa powder until blended, then add a pinch of salt, vanilla, and about 1/4 cup of milk. Remove from heat, whisk in powdered sugar, and add a little extra milk if needed to reach a slightly pourable consistency.
Use a fork or skewer to poke holes across the top of the brownies, then pour the frosting evenly over the warm bars so it seeps into the holes and across the surface. Allow the frosting to set before slicing and serving for clean squares with a glossy chocolate top.
Allow the frosting to firm up completely before removing the bars from the pan to keep the pieces intact. Frosted brownies add richness and a silky chocolate finish to the peanut-buttery interior.
Recipe Highlights & Tips
- Prep time: 10 minutes; Cook time: about 15–20 minutes; Resting time: 30 minutes.
- Makes 24 servings. Calories (unfrosted): about 260 per brownie; with frosting approximately 344 per serving.
- If using unsalted peanut butter, add 1/4 teaspoon salt to the batter to balance flavors.
- For a thinner frosting, add milk a tablespoon at a time until you reach the desired consistency.
Printable Recipe Card
- 1 cup creamy peanut butter (not natural)
- 1 stick (1/2 cup) butter, softened
- 1 cup light brown sugar (packed)
- 1/2 cup granulated sugar
- 4 large eggs
- 1 teaspoon vanilla extract
- 1 cup unsweetened cocoa powder
- 1 cup all-purpose flour
- 1 1/4 cups semisweet chocolate chips
- 1/2 cup cocktail peanuts, finely chopped
- 6 Tablespoons butter (3/4 stick)
- 4 Tablespoons unsweetened cocoa powder
- Pinch of salt
- 1 teaspoon vanilla extract
- 12 ounces powdered sugar
- 1/4 cup low-fat milk (1%), more if needed to thin
- Preheat oven to 350°F. Lightly grease a 9×13 baking pan.
- Cream peanut butter, butter, brown sugar, and granulated sugar with an electric mixer on high until blended. Turn mixer to medium and add vanilla and eggs one at a time, beating well after each addition.
- Remove beaters. Stir in cocoa powder, flour, chocolate chips, and chopped peanuts by hand until fully combined.
- Spread batter evenly in prepared pan and bake on the center rack for 15–20 minutes, or until a toothpick inserted into the center comes out clean and the surface feels firm.
- For unfrosted brownies: slice into 24 pieces while still hot and allow to cool in the pan to room temperature before removing.
- For frosted brownies: slice while hot. To make frosting, melt butter on low heat, remove from heat, add cocoa and stir. Add salt, vanilla, and 1/4 cup milk; stir by hand, then add powdered sugar and mix until smooth. Add more milk if needed to achieve a slightly pourable consistency. Poke holes in the brownie tops and pour frosting over the surface. Allow frosting to set before serving.
Nutrition estimate (unfrosted): 260 kcal per serving. With the included frosting, calories rise to approximately 344 per serving. If using unsalted peanut butter, add 1/4 teaspoon salt to the batter.
These chocolate peanut butter brownies are a crowd-pleasing dessert for potlucks, family gatherings, or a cozy night in. They pair well with a glass of cold milk or a scoop of vanilla ice cream for extra indulgence. Enjoy!