Triple Chocolate Sourdough Brownies (Printable)

Rich, fudgy chocolate squares with sourdough for unique chew and intense chocolate flavor.

# What You Need:

→ Chocolate & Cocoa

01 - 4 oz bittersweet chocolate, chopped
02 - 2 oz milk chocolate, chopped
03 - 1/4 cup unsweetened Dutch-process cocoa powder

→ Fats

04 - 1/2 cup unsalted butter, cubed

→ Sugar

05 - 1 cup granulated sugar
06 - 1/4 cup light brown sugar, packed

→ Sourdough & Liquids

07 - 1/2 cup sourdough discard, unfed
08 - 2 large eggs, room temperature
09 - 1 teaspoon pure vanilla extract

→ Dry Ingredients

10 - 2/3 cup all-purpose flour
11 - 1/2 teaspoon fine sea salt

→ Chocolate Mix-ins

12 - 1/3 cup semi-sweet chocolate chips or chunks

# How To Make It:

01 - Preheat oven to 350°F. Line an 8-inch square baking pan with parchment paper, leaving overhang for easy removal.
02 - Combine bittersweet chocolate, milk chocolate, cocoa powder, and butter in a heatproof bowl. Melt over simmering water or in microwave using 30-second bursts, stirring until smooth. Cool slightly.
03 - In a large bowl, whisk together granulated sugar, brown sugar, eggs, and vanilla extract until pale and thick, approximately 2 to 3 minutes.
04 - Whisk sourdough discard into the cooled chocolate mixture until fully incorporated.
05 - Add chocolate mixture to egg-sugar mixture and mix gently until combined.
06 - Sift flour and salt together, then fold gently into batter using a spatula until just combined. Avoid overmixing.
07 - Gently fold chocolate chips or chunks into batter.
08 - Pour batter into prepared pan and smooth the top with a spatula.
09 - Bake for 28 to 32 minutes, until edges are set and center is slightly wobbly. Do not overbake to maintain chewy texture.
10 - Cool completely in pan on wire rack before lifting out and slicing into squares.

# Expert Suggestions:

01 -
  • The sourdough discard adds a subtle tang that deepens the chocolate flavor without tasting sour, making these taste far more sophisticated than they have any right to.
  • You finally have a guilt-free way to use that starter you keep meaning to feed, turning kitchen waste into something genuinely delicious.
  • The texture sits in this magical zone between fudgy and chewy—dense enough to feel indulgent but tender enough that you can eat more than one without feeling heavy.
02 -
  • The center will seem underbaked when you pull it from the oven, and you'll second-guess yourself—don't. The carryover heat continues cooking as it cools, and that wobble firms up into the perfect fudgy texture that's different from truly undercooked.
  • Slicing warm brownies tears them apart, which I learned the hard way on that first batch; chill them for at least an hour (or overnight) and use a hot knife wiped between cuts for clean edges.
03 -
  • Make these the day before serving—they slice cleaner, taste slightly better as flavors meld, and you remove the temptation to eat them while still warm (though warm is delicious, chilled is sharper).
  • If your sourdough discard is particularly active or bubbly, use it immediately after feeding; sluggish, room-temperature discard from the back of the fridge is actually ideal because it contributes moisture without adding excessive fermentation.
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