Best Sourdough Discard Chocolate Brownies

Last Updated on November 8, 2025 by Jamie Saechao

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These rich and fudgey sourdough discard chocolate brownies are a decadent and fun way to use your extra sourdough!

Made with cocoa powder and two kinds of chocolate chips, these brownies are the best gooey, chewy treats.

This easy sourdough recipe is the perfect quick dessert, bursting with flavor that will satisfy your chocolate cravings! These double chocolate brownies are perfect for Christmas parties, holiday baking days, and gifting to friends or family.

Flavored with cocoa powder, loaded with chocolate chips, and offset with tangy sourdough discard, these are (in my humble opinion) the absolute best brownies.

The batter is velvety smooth and comes together in just a few minutes, and the brownies only take 30 minutes to bake.

For more sourdough chocolate desserts, try these double chocolate cookies, chocolate croissant bread, chocolate zucchini muffins, chocolate focaccia, sourdough chocolate cake, sourdough chocolate chip cookies.

Ingredients

• All purpose flour
• Baking powder
• Salt – if using salted butter you can omit the salt.
• Cocoa: Use natural cocoa powder or dutch-processed cocoa powder. Dutch cocoa will give your richer, more intense chocolate brownies.
• Unsalted butter
• Oil – I use avocado oil but any type of vegetable oil can be used.
• Granulated sugar
• 2 large eggs
• 1 large egg yolk
• 1.5 tsp vanilla extract
• 1/3 cup sourdough discard (flat, runny sourdough starter)
• Chocolate chips
• Mini chocolate chips *optional, for sprinkling on top of baked brownies.

What Is Sourdough Discard?

Sourdough discard is the flat, runny portion of sourdough starter that is often thrown out when feeding a starter. It is sourdough starter that is not active. You can use room temperature or refrigerated starter for this recipe.

Best Baking Pan To Use

• I recommend using a 9×9 aluminum baking pan for this recipe. However, you can use a glass baking dish- the brownies will just need to bake for an additional 7-10 minutes.

If you’d like thicker brownies, use an 8×8 pan. You will need to increase the bake time by 5-10 minutes.

Recipe Tips

• To measure the flour, scoop it out with a spoon and pour it into the measuring cup, and then level off with the back of a butter knife. 
• Sprinkle a bit of chunky sea salt on the top for a gourmet feel to this decadent dessert.
• For soft and gooey brownies, do not over-bake. Take them out when the edges are firm but there is still a little bit of doughiness, or wiggle, in the middle of the pan!
• The mini chocolate chips add a LOT of fun texture and flavor to this recipe (my husband says he loves them)… so omit at your own risk!
• This batter is very thick and requires scooping instead of pouring into the pan.

How To Make Fudgy Sourdough Brownies

Prep: Preheat the oven to 350 degrees F.  Grease an 9×9 aluminum pan with butter or cooking oil, then press the parchment paper into the pan, allowing some of the parchment to hang over the edge so you can easily remove the brownies. 

In a medium bowl, whisk together the flour, cocoa, salt, and baking powder.

Next, combine the butter, oil, and 1/4 cup of the sugar in a medium saucepan. Heat over medium heat on a stovetop, stirring frequently, until butter is completely melted, then remove from heat and set aside.

In a large mixing bowl, combine the vanilla, eggs, egg yolk, and 1 cup sugar. Whisk very well, about 1 minute. Slowly pour the warmed butter mixture into the eggs, whisking well as you go.

Add the flour mixture, sourdough starter, and semi-sweet chocolate chips to the wet ingredients, mixing until just combined. Do not overmix!

Pour the batter into the pan (it will be very thick!), then smooth down. Bake for 27-30 minutes or until the edges are firm. Remove the brownies and sprinkle the mini-chocolate chips over the top

Let cool completely before slicing.

Don’t over bake: For the best fudgey brownies, do not over bake. Remove your brownies from the oven when the edges are firm but the middle is still slightly underbaked.

How To Store

• Let cool completely before storing
• Store brownies at room temperature in an airtight container for 3-5 days.
• To freeze, slice brownies, then wrap individually with plastic and place in a freezer safe container. Freeze for up to 3 months.

As an avid chocolate lover, I think we my have created the perfect brownie recipe! My daughter, the pie princess, had a huge role in developing this discard recipe.
We hope you love it!

P.S. As a busy mom, I am obsessed with easy recipes.  Check out my three ingredient fudge, easy sourdough bread for newbies, and simple chocolate truffles.