Sourdough Cosmic Chocolate Brownies (Printable Version)
Fudgy, tangy sourdough chocolate brownies topped with chocolate chips and rainbow sprinkles.
# What You Need:
→ Wet Ingredients
01 - 1/2 cup unsalted butter, melted
02 - 7 oz dark chocolate (70% cacao), chopped
03 - 3/4 cup granulated sugar
04 - 1/4 cup packed light brown sugar
05 - 2 large eggs, room temperature
06 - 1 teaspoon pure vanilla extract
07 - 1/2 cup active sourdough starter (100% hydration, unfed or discard)
→ Dry Ingredients
08 - 2/3 cup all-purpose flour
09 - 1/4 cup unsweetened cocoa powder
10 - 1/2 teaspoon fine sea salt
→ Cosmic Topping
11 - 3/4 cup mini chocolate chips or candy-coated chocolate pieces
12 - 3 tablespoons rainbow sprinkles
# How to Make It:
01 - Preheat oven to 350°F. Line an 8x8-inch baking pan with parchment paper, leaving an overhang on two sides for easy removal.
02 - Combine the unsalted butter and chopped dark chocolate in a heatproof bowl. Set over a pot of simmering water (double boiler) or microwave in 30-second intervals, stirring between each, until completely smooth. Let cool for 5 minutes.
03 - Whisk the granulated sugar and brown sugar into the melted chocolate mixture until glossy and well blended. Add the eggs one at a time, whisking thoroughly after each addition. Stir in the vanilla extract.
04 - Gently fold the sourdough starter into the batter using a spatula until fully incorporated and no streaks remain.
05 - Sift the all-purpose flour, cocoa powder, and fine sea salt together into a separate bowl. Gradually fold the dry mixture into the wet batter until just combined. Avoid overmixing to keep the brownies tender.
06 - Pour the batter into the prepared baking pan and spread it into an even layer. Scatter the mini chocolate chips or candy-coated pieces evenly across the surface, then generously sprinkle with rainbow sprinkles.
07 - Bake on the center rack for 28 to 32 minutes, or until a toothpick inserted into the center comes out with moist crumbs clinging to it. Avoid overbaking for the fudgiest texture.
08 - Transfer the pan to a wire rack and let the brownies cool completely in the pan. Once fully set, use the parchment overhang to lift the slab out and cut into 16 squares.
# Expert Advice:
01 -
- The sourdough starter adds a subtle tanginess that makes the chocolate taste deeper and more complex without anyone guessing your secret.
- Rainbow sprinkles on top turn an already incredible brownie into something that makes people smile before they even take a bite.
02 -
- Underbaking slightly is always better than overbaking because the brownies will continue to set as they cool in the pan.
- If your sourdough starter is very liquidy, the batter may need an extra minute in the oven, so watch the edges closely.
03 -
- If you do not have sourdough starter, substitute 100 grams of plain Greek yogurt for a similar tangy richness.
- Always check your sprinkle and candy labels for allergens since ingredients can vary widely between brands.