Ingredients

2 large eggs (room temperature)

1 large egg yolk (room temperature)

1½ cups brown sugar (light or dark, packed)

10 tablespoons unsalted butter

½ cup chocolate chunks or chopped baking chocolate (bittersweet or dark, high quality)

½ cup sourdough discard (unfed sourdough starter)

¾ cup all-purpose flour (weighed in grams or spooned and leveled)

½ cup cocoa powder

½ teaspoon salt

1 cup semi-sweet chocolate chips (divided: ⅔ in the batter, ⅓ for topping)

Instructions

Step 1: Preheat the oven to 350°F and line a 9-inch square pan with parchment paper.

Step 2: In a large bowl, whisk together the eggs, egg yolk, and brown sugar until the mixture is light and airy, about 4 to 5 minutes.

Step 3: In a microwave-safe bowl, melt the butter with the ½ cup of chocolate chunks. Allow it to cool slightly, then whisk it into the egg and sugar mixture for 1 to 2 minutes. Stir in the sourdough discard until combined.

Step 4: In a medium bowl, whisk together the flour, cocoa powder, salt, and ⅔ cup of chocolate chips. Using a spatula, fold the dry ingredients gently into the wet ingredients just until there are no flour streaks left.

Step 5: Spread the brownie batter evenly into the prepared pan. Sprinkle the remaining ⅓ cup of chocolate chips on top. Bake in the oven for 22 to 27 minutes, until the edges are set and the center has a shiny, crackly top.

Step 6: Let the brownies cool completely in the pan on a wire rack. Once cooled, remove from the pan, slice into squares, and enjoy!

Tips & Variations

Use high-quality chocolate for the best flavor and texture.

If you prefer a nutty twist, fold in ½ cup chopped walnuts or pecans with the dry ingredients.

Make sure eggs and egg yolk are at room temperature for a better batter texture.

For an extra fudgy result, slightly underbake the brownies and let them cool fully before slicing.

Feel free to swap the semi-sweet chocolate chips with dark or milk chocolate chips according to your preference.

FAQs

Can I use a different type of flour?

All-purpose flour works best for the right texture, but you can substitute with gluten-free flour blends if needed. Just keep in mind the texture and baking time might vary slightly.

What is sourdough discard and why is it used?

Sourdough discard is the unfed portion of sourdough starter that bakers remove before feeding. It adds moisture, flavor complexity, and helps create a tender crumb in baked goods like these brownies without affecting rise.