Ingredients:

  • 1 cup (225g) unsalted butter, melted and warm
  • 1.5 cups (300g) granulated sugar
  • 0.5 cup (100g) light brown sugar, packed
  • 0.75 cup (75g) Dutch-processed cocoa powder, sifted
  • 0.5 tsp fine sea salt
  • 0.5 cup (125g) sourdough discard, room temperature
  • 2 large eggs, room temperature
  • 1 tbsp vanilla extract
  • 0.75 cup (95g) all-purpose flour
  • 1 cup (170g) semi-sweet chocolate chips

Instructions:

  1. Preheat your oven to 350°F (180°C) and line a 9x9 inch square baking pan with parchment paper, leaving an overhang on the sides for easy removal.
  2. In a large microwave-safe glass bowl, combine the warm melted butter, granulated sugar, and light brown sugar. Whisk vigorously by hand for 2 minutes to partially dissolve the sugar and begin emulsification.
  3. Add the sourdough discard, eggs, and vanilla extract to the butter mixture. Whisk until the batter is smooth and fully integrated.
  4. Whisk in the sifted Dutch-processed cocoa powder and sea salt until no lumps remain and the batter is deep mahogany in color.
  5. Switch to a silicone spatula and gently fold in the all-purpose flour and chocolate chips until just combined. Do not overmix to ensure a fudgy texture.
  6. Pour the batter into the prepared pan and smooth the top. Bake for 25 minutes or until a toothpick inserted into the center comes out with a few moist crumbs.