# What You’ll Need:
→ Chocolate & Cocoa
01 - 3.5 oz bittersweet chocolate (60–70% cacao), chopped
02 - 1.75 oz milk chocolate, chopped
03 - 1.75 oz white chocolate, chopped
04 - 1/4 cup unsweetened cocoa powder
→ Sourdough & Wet Ingredients
05 - 1/2 cup sourdough starter (100% hydration, unfed or discard)
06 - 1/2 cup unsalted butter, cubed
07 - 2 large eggs
08 - 1 teaspoon vanilla extract
09 - 2 tablespoons strong brewed espresso or 1 tablespoon instant espresso powder dissolved in 2 tablespoons hot water
→ Dry Ingredients
10 - 3/4 cup granulated sugar
11 - 1/4 cup light brown sugar, packed
12 - 3/4 cup all-purpose flour
13 - 1/2 teaspoon fine sea salt
# Method:
01 - Preheat oven to 350°F. Line an 8x8-inch baking pan with parchment paper, leaving overhang on two sides for easy removal.
02 - Combine bittersweet chocolate and butter in a heatproof bowl. Set bowl over a saucepan of gently simmering water, stirring frequently until smooth and fully melted. Remove from heat and cool slightly.
03 - Whisk both sugars into the melted chocolate mixture until combined. Add eggs one at a time, whisking thoroughly after each addition until fully incorporated.
04 - Stir vanilla extract and espresso into the egg mixture until evenly distributed.
05 - Fold sourdough starter into the chocolate mixture using a spatula until no streaks remain.
06 - Sift flour, cocoa powder, and salt together into a separate bowl.
07 - Gently fold dry ingredients into the wet mixture using minimal strokes—stop when no flour streaks are visible to avoid overdeveloping gluten.
08 - Fold milk chocolate and white chocolate pieces into the batter until evenly distributed.
09 - Pour batter into the prepared pan and smooth the surface with a spatula.
10 - Bake for 32 to 36 minutes until the center is just set. A toothpick inserted in the middle should emerge with moist crumbs, not wet batter.
11 - Allow brownies to cool completely in the pan before lifting out using parchment overhang. Slice into 12 equal squares and serve at room temperature or slightly chilled.
