Ingredients:

  • 1/2 cup (113g) butter, melted
  • 3/4 cup (150g) granulated sugar
  • 1 large egg, room temperature
  • 1 tsp vanilla extract
  • 1 cup (125g) all-purpose flour
  • 1/2 cup (45g) unsweetened cocoa powder
  • 1/2 tsp baking soda
  • 1/4 tsp salt
  • 1/2 cup (128g) creamy peanut butter
  • 1/4 cup (56g) butter, softened
  • 1/2 cup (100g) brown sugar, packed
  • 1 large egg, room temperature
  • 1 cup (125g) all-purpose flour
  • 1/2 tsp baking soda
  • 1/4 tsp salt

Instructions:

  1. Prepare the brownie dough by whisking melted butter and cocoa powder together, then fold in sugar, egg, vanilla, flour, baking soda, and salt until a thick dough forms.
  2. In a separate bowl, prepare the peanut butter dough by creaming softened butter and peanut butter with brown sugar, then mixing in the egg and dry ingredients.
  3. Master the marble technique by taking 1 tablespoon of each dough, pressing them together, and giving them a single short twist to create a swirl pattern without over-mixing.
  4. Place portioned dough balls on a tray and refrigerate for 30 minutes to stabilize the fats.
  5. Preheat oven to 350°F (175°C) and line a baking sheet with parchment paper.
  6. Bake cookies for 9–11 minutes until the edges are set but the centers remain slightly soft.
  7. Allow cookies to cool on the pan to firm up before serving.