Ingredients:

  • 1 cup (226g) Unsalted Butter, cubed
  • 8 ounces (225g) High-Quality Dark Chocolate (70% Cacao), roughly chopped
  • 1 ¾ cups (350g) Granulated Sugar
  • ½ cup (100g) Light Brown Sugar, packed
  • 4 large Eggs, room temperature
  • 1 tablespoon Pure Vanilla Extract
  • 1 teaspoon Instant Espresso Powder
  • 1 teaspoon Fine Sea Salt
  • 1 cup (120g) All-Purpose Flour, spooned and leveled
  • ¼ cup (25g) Unsweetened Cocoa Powder, sifted

Instructions:

  1. Preheat oven to 350°F (175°C). Line an 8x8 inch metal baking pan with parchment paper, leaving an overhang on two sides to act as handles.
  2. Combine butter and chopped dark chocolate in a heatproof bowl. Gently melt using a double boiler or in 30-second bursts in the microwave, stirring until completely smooth. Let cool for 5 minutes.
  3. Whisk the granulated sugar, brown sugar, espresso powder, and salt into the slightly cooled chocolate mixture until thoroughly combined.
  4. Add the eggs one at a time, whisking vigorously for a full 60 seconds after each addition until the mixture becomes lighter in color and glossy. Whisk in the vanilla extract.
  5. Sift the flour and cocoa powder over the wet mixture. Using a rubber spatula, gently fold until just combined. Stop mixing the moment no dry streaks remain; do not overmix.
  6. Pour the batter into the prepared pan and smooth the top. Bake for 30–35 minutes. Test with a toothpick 1 inch from the edge; it should come out with moist, fudgy crumbs attached, not wet batter.
  7. Remove from the oven and cool completely in the pan on a wire rack for a minimum of 2 hours before lifting out and slicing. This cooling step is essential for clean, fudgy cuts.