Buckeye Brownies with a Peanut Butter Buttercream Frosting

Where to begin with these…hmm.  Well for starters,  my chocolate – peanut butter craving was beyond satisfied with this recipe!  The moist chocolateyness (I now dub this a real word) of the brownie combined with peanut butter gooeyness was perfection.  I promise you, the peanut butter filling of this brownie tasted identical to the inside of a reese’s peanut butter cup. Seriously   At one point I caught myself making a peanut butter ball and eating the next peanut butter ball, I was like a child who just couldn’t stop.

I was a little concerned about putting a peanut butter frosting on these – I thought it might be overkill. Thankfully, I was so WRONG! This frosting turned out fluffy and light – it completed the perfection of the brownie.

If you are a peanut butter and/or chocolate lover of any sorts – then try this recipe, right now. I promise they will not disappoint.  Yum.  I think I’ll go eat another one right now… make it stop!


For the filling:

  • 1 cup powdered sugar
  • ¾ cup creamy peanut butter
  • 4 tablespoons. unsalted butter, at room temperature
  • ½ tsp. vanilla extract

For the cupcakes:

  • 1 2/3 cups all-purpose flour
  • ¾ cup cocoa powder
  • 1 teaspoon baking soda
  • ½ tsp. salt
  • 1 cup sour cream
  • 2 tbsp. milk
1 tsp. vanilla extract
  • 8 tablespoons, unsalted butter, at room temperature
  • ½ cups sugar
2 large eggs

For the frosting:

  • 1/3 cup solid vegetable shortening
  • 1/3 cup butter
  • 3/4 cup peanut butter
  • 1 teaspoon vanilla extra
  • 1/2 teaspoon butter flavoring
  • 5 cups confectioners’ sugar, sifted
  • 4 tablespoons milk


Preheat the oven to 350° F. Line two cupcake pans with paper liners (24).

To make the filling:

1. Combine the powdered sugar, peanut butter, butter and vanilla extract in a bowl. Beat with an electric mixer on medium speed until well combined

2. Roll the mixture into 1-inch balls (at least 24) and set aside on a baking sheet.

To make the batter:

1. Combine the flour, cocoa powder, baking soda and salt in a medium bowl; whisk together and set aside


In a liquid measuring cup, stir together the sour cream, milk and vanilla extract

3. In a large bowl combine the butter and sugar, and beat on medium-high speed until light and fluffy, about 2 minutes. 

Beat in the eggs one at a time, scraping down the bowl as needed. With the mixer on low speed, alternately add the dry ingredients and the sour cream mixture, beginning and ending with the dry ingredients. Mix just until incorporated

4. Spoon a tablespoon or two of batter into the bottom of each cupcake liner. Place a ball of the peanut butter filling in each cupcake well and top with the remaining batter so that all the cups are filled

5. Bake for 18-22 minutes, or until a toothpick inserted in the center comes out clean. Allow to cool in the pan for 5-10 minutes, then transfer to a wire rack to cool completely.

To make the frosting:

1 .Cream shortening and butter with electric mixer. Add peanut butter and vanilla.

2. Gradually add sugar, one cup at a time, beating well on medium speed. Scrape sides and bottom of bowl often. When all sugar has been mixed in, icing will appear dry.

3. Add milk, one tablespoon at a time, and beat at medium speed until light and fluffy.

Frost cooled brownie cupcakes as desired.

Modified from: The Kitchen Door