Peanut Butter Cup Brownies

Brownies sliced into squares on a wooden board covered in parchment paper.
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5 from 1 review

The ULTIMATE rich, oooy-gooey, and chocolatey brownies, with perfectly-crinkled tops and chunks of peanut butter cups in every bite. These no flour brownies are also naturally gluten-free - and SO fudgy too!

  • Author: Alexandra
  • Prep Time: 25 minutes
  • Cook Time: 25 minutes (up to 30)
  • Total Time: 50 minutes (up to 55)
  • Yield: 9-12 1x
  • Category: brownies
  • Method: baking
  • Cuisine: American
  • Diet: Gluten Free


  • 3 ounces (6 tablespoons) butter, cubed
  • 6 ounces bittersweet chocolate, chopped 
  • 4 5/8 ounces (2/3 cup) granulated sugar
  • 2 large eggs, room temperature
  • 1 tablespoon vanilla extract
  • 7/8 ounce (1/4 cup) cocoa powder
  • 3 tablespoons corn starch
  • 1/4 teaspoon salt
  • 5 1/8 ounces (1 generous cup) chopped peanut butter cups, plus extra for sprinkling on top


  1. Preheat oven  to 350ºF and line an 8" square pan with parchment paper or aluminum foil. If using foil, grease with nonstick spray.
  2. Melt butter and chocolate: Combine butter and chocolate in a microwave-safe bowl. Microwave for 30-second increments, stirring in between, until smoothly melted. 
  3. Combine the dry ingredients: In a small mixing bowl, whisk together the cocoa powder, corn starch and salt.
  4. Whip eggs and sugar: In the bowl of a stand mixer fitted with the wire whip attachment, begin beating the eggs on medium speed. While beating, slowly pour in sugar. Increase speed to medium-high and continue beating for several minutes until mixture is light in color and ribbons down from the beater when lifted. Wipe down bowl and beater as needed.
  5. Add remaining ingredients: With mixer on low speed, add the butter/chocolate mixture and vanilla extract, mixing in until combined. Add the dry ingredients and peanut butter cups and fold in with a rubber spatula just until evenly incorporated.
  6. Transfer to pan: Pour batter into prepared pan and use spatula to smooth out top surface. If desired, sprinkle with extra peanut butter cups (you can also do this after baking if preferred). 
  7. Bake brownies in preheated oven for 25-30 minutes, until a toothpick inserted into the center comes out with only a few moist crumbs, and edges are slightly pulling away from sides of pan.
  8. Cool and slice. Place pan over a wire rack and allow brownies to cool completely. Then, use foil/parchment to lift from pan. Slice with a sharp knife. For even cleaner slicing, transfer to fridge for 30-60 minutes before slicing.


Ingredients notes:

  • Salted or unsalted butter can be used.
  • Chopped chocolate can be substituted with chocolate baking chips.
  • Regular or Dutch-process cocoa powder will work for this recipe. 
  • Reese's Minis can also be used and do not need to be chopped. Or, sub your favorite candy of choice!

For dairy-free brownies:

Storage and shelf life:

  • Brownies are best if stored in an airtight container at room temperature. They will keep for 5-7 days.

Recipe adapted from Running with Spoons