# What You Need:
→ Chocolate & Fats
01 - 6 oz dark chocolate (60–70% cocoa), chopped
02 - 1/2 cup unsalted butter, cubed
03 - 1/4 cup neutral oil (canola or vegetable)
→ Sugars
04 - 1 cup granulated sugar
05 - 1/2 cup light brown sugar, packed
→ Eggs & Sourdough
06 - 2 large eggs, at room temperature
07 - 1 large egg yolk
08 - 1/2 cup sourdough discard, unfed and at room temperature
09 - 1 teaspoon pure vanilla extract
→ Dry Ingredients
10 - 1/2 cup all-purpose flour
11 - 1/3 cup unsweetened Dutch-process cocoa powder
12 - 1/2 teaspoon fine sea salt
→ Topping
13 - Flaky sea salt, for sprinkling
# Directions:
01 - Preheat oven to 350°F. Line an 8x8 inch baking pan with parchment paper, leaving overhang on two sides for easy removal.
02 - In a heatproof bowl set over a pan of simmering water, melt chocolate and butter together, stirring until smooth. Remove from heat and whisk in oil until fully incorporated.
03 - Whisk in both granulated and brown sugars until the mixture becomes glossy and well combined.
04 - Add eggs and egg yolk one at a time, whisking thoroughly after each addition. Whisk vigorously for 1–2 minutes until the mixture becomes thick and shiny.
05 - Stir in sourdough discard and vanilla extract until fully incorporated into the batter.
06 - Sift together flour, cocoa powder, and fine sea salt. Fold gently into the wet mixture using a spatula until just combined; avoid overmixing.
07 - Pour batter into the prepared pan and smooth the top surface evenly. Sprinkle generously with flaky sea salt.
08 - Bake for 28–32 minutes, or until the edges are set but the center remains slightly soft. A toothpick inserted should come out with moist crumbs, not wet batter.
09 - Cool completely in the pan on a wire rack before lifting out using the parchment overhang. Slice into 16 equal squares.