# What You Need:
→ Chocolate & Fats
01 - 6 oz dark chocolate (60–70% cocoa), chopped
02 - ½ cup unsalted butter, cubed
03 - ¼ cup neutral oil (canola or vegetable)
→ Sugars
04 - 1 cup granulated sugar
05 - ½ cup light brown sugar, packed
→ Eggs & Sourdough
06 - 2 large eggs, at room temperature
07 - 1 large egg yolk
08 - ½ cup sourdough discard, unfed and at room temperature
09 - 1 teaspoon pure vanilla extract
→ Dry Ingredients
10 - ½ cup all-purpose flour
11 - ⅓ cup unsweetened Dutch-process cocoa powder
12 - ½ teaspoon fine sea salt
→ Topping
13 - Flaky sea salt for sprinkling
# How-To Steps:
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 chopped chocolate and butter together, stirring until smooth. Remove from heat and whisk in neutral oil.
03 - Whisk in granulated sugar and light brown sugar until glossy and fully combined.
04 - Add whole eggs and egg yolk one at a time, whisking well after each addition. Whisk vigorously for 1–2 minutes until mixture is thick and shiny.
05 - Stir in sourdough discard and vanilla extract until fully incorporated.
06 - Sift in flour, cocoa powder, and fine sea salt. Fold gently with a spatula until just combined; do not overmix.
07 - Pour batter into prepared pan and smooth the top. Sprinkle generously with flaky sea salt.
08 - Bake for 28–32 minutes, or until the edges are set but the center is still slightly soft. A toothpick inserted should come out with moist crumbs.
09 - Cool completely in the pan on a wire rack before lifting out and slicing into 16 squares.