Sourdough Brownies (Discard Recipe)

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Hi Bold Bakers!

WHY YOU’LL LOVE THIS RECIPE: My fudgy Sourdough Brownies (Discard Recipe) are outrageously intense, chocolatey, and craveable thanks to a surprising secret ingredient. If you feel like you’ve sampled every type of brownie out there, you’re in for a delicious surprise! And if you’re not a sourdough baker, learn how easy it is to whip up a starter that will open up a new world of flavor.

• Serious flavor boost: The starter’s subtle tang enhances the chocolate beautifully in the brownies and other sourdough dessert recipes.
• Luxe texture: My brownies are soft, tender, and decadently dense.
• Casual or fancy: A cooled brownie with a glass of milk is heavenly, but you can also dress them up with ice cream, whipped cream, or a dessert sauce.
• Ready in an hour: Getting a gourmet-level treat so quickly is a serious win.
• Get ready for compliments! These are rich brownies for serious chocolate lovers. Make them once, and you’ll be baking them on repeat.

A recipe with a secret ingredient is so much fun, but using sourdough discard—leftover sourdough starter, a fermented mixture of flour and water—is more than a gimmick in this brownie recipe! I obviously adore brownies (just check out the dozens of Bigger Bolder Baking recipes), so when I was developing this recipe, I wanted sourdough discard to genuinely improve the brownies. I was thrilled at the results!  Sourdough discard adds depth of flavor that you can’t buy off the shelf, and it adds moisture and creates an irresistibly tender, fudgy crumb. For the ultimate flavor and fudgy texture, follow my steps for 100 Hour Brownies and apply them to this recipe. The extra time chilling with really set these brownies apart from other recipes. If you don’t have sourdough starter, I’ve got you covered with step-by-step directions that will launch you into the flavorful world of sourdough baking.

Table of Contents

• What are Sourdough Brownies?
• Tools You Need
• Key Ingredients and Substitutes
• How to Make Sourdough Brownies
• Gemma’s Pro Chef Tips
• Make Ahead and Storage Instructions
• FAQs
• More Brownie Recipes

What are Sourdough Brownies?

Sourdough Brownies are fudgy, rich chocolate brownies made with sourdough discard (unfed sourdough starter). This ingredient adds deeper flavor, with subtle tang that enhances the chocolate, and moisture for a plush, velvety texture. Bread leavened with wild yeast is an ancient food. Although sourdough starter was probably always used, it has recently become a popular ingredient for enhancing the flavor and texture of savory baked goods and sourdough desserts.  These sourdough discard brownies are a delightful snack, a dessert on their own, or the base of a trifle or bread pudding.

Tools You Need

• Mixing bowls
• Measuring spoons
• Measuring cups
• Glass measuring jug
• Kitchen scale (optional)
• 8-inch (20-cm) square baking pan
• Parchment paper
• Microwave-safe bowl
• Whisk
• Stand mixer (optional) or electric hand mixer

Key Ingredients and Substitutes

Bittersweet chocolate

• Bittersweet chocolate is the primary flavor. Bittersweet chocolate, which has 63-72% cocoa solids, makes the brownies intensely flavored and sweet without being cloying.
• Using melted chocolate creates a fudgy structure.
• Please use chocolate that has been chopped from a good-quality chocolate bar. Chocolate chips won’t melt smoothly because they contain stabilizers that help them hold their shape.
• Substitute: Use the same amount of chopped semi-sweet chocolate.

Butter

• Butter gives the sourdough starter brownies moisture, richness, and flavor.
• Substitute: You can use 6 tablespoons (3 oz/85 g) of coconut or avocado oil in place of the butter. The brownies will come out softer.

Dutch-processed cocoa powder

• Dutch-processed cocoa powder deepens the chocolate flavor and gives the sourdough brownie a rich color.
• Substitute: You can use the same amount of natural cocoa in a pinch, but note that the brownies will be slightly drier and chewier and won’t have a dark, rich color.

Eggs

• Eggs bring the ingredients together into a cohesive batter and give the brownies structure.
• Substitute: In place of the eggs, you can use 1/2 cup (4 oz/120 g) of full-fat Greek yogurt.
  • Note that if you make this change, the brownies might be a bit denser.

Egg yolk

• The extra yolk adds fat, enhancing the moist, velvety mouthfeel.
• Substitute: If you prefer, use 2 tablespoons of full-fat Greek yogurt for the egg yolk.

Granulated sugar

• Granulated sugar sweetens the brownies.
• Additionally, granulated sugar adds moisture and contributes to creating a crackly, shiny top.
• Substitute: If you’d like a more caramelized flavor, you can use an equal amount of brown sugar in place of the granulated sugar.

Dark brown sugar

• The molasses in dark brown sugar gives these brownies a note of warmth.
• Importantly, dark brown sugar adds moisture, creating fudgy centers.
• Substitute: Use light brown sugar if you prefer.

Salt

• Salt makes the flavors pop, and especially enhances the chocolate.
• If you don’t use salt, the brownies will taste bland.

Sourdough starter discard

• Sourdough starter discard gives the brownies a subtle, tantalizing tang and a deliciously complex flavor.
• Importantly, sourdough discard (unfed starter) relaxes the gluten slightly in sourdough discard desserts, resulting in a tender crumb.
• Substitute: The sourdough discard adds moisture and a touch of acidity to the brownies. If you don’t have discard, you can use 1/2 cup (4 fl oz/120 ml) of buttermilk.
  • Note that if you make this change, the flavor won’t be as layered and complex.

Vanilla extract

• Warmly sweet vanilla rounds out the flavors and brings out the chocolate.
• Substitute: The same amount of  Vanilla Bean Paste also works well here.

All-purpose flour

• Flour gives the brownies structure.
• Substitute: For gluten-free brownies, use an equal amount of a 1:1 gluten-free baking mix, like my Easy Almond Flour Baking Mix or another gluten free flour.

How to Make Sourdough Brownies

1. Prepare to bake: Preheat the oven to 350°F (180°C). Butter and line an 8-inch (20-cm) square baking pan with parchment paper. Set aside.
2. Melt chocolate with butter and cocoa: In a medium microwave-safe bowl, melt 2 cups (12 oz/340 g) of chocolate, butter, and cocoa powder in the microwave for 60 to 90 seconds, or until melted. Whisk to bring the ingredients together, then set aside to cool.

3. Whip eggs and sugar: In the bowl of a stand mixer fitted with a whisk attachment (or with a hand-held electric mixer and a large bowl), whip the eggs, yolk, granulated sugar, and brown sugar for 4 to 5 minutes on high speed, until thick and pale.

4. Combine chocolate mixture with other ingredients: Lower the speed to medium-low and mix in the chocolate mixture, sourdough starter, vanilla extract, and salt.

5. Add flour and chopped chocolate: Lastly, add in the flour until just combined, then spread into your prepared pan. Sprinkle on the remaining ⅓ cup (2 oz/57 g) chopped chocolate.

6. Bake: Bake for 35-40 minutes, or until just barely set in the center.

7. Cool: Let cool completely before cutting into nine squares.

FULL (PRINTABLE) RECIPE BELOW! 

Gemma’s Pro Chef Tips

• I use Dutch-processed cocoa in this rich and fudgy recipe because there is no baking soda to neutralize the acid in natural cocoa powder. Natural cocoa powder can be used, but it will result in slightly drier, chewier brownies that are lighter in color.
• You can make this recipe without a stand mixer or a hand mixer: Just be sure to vigorously whisk the eggs, egg yolk, granulated sugar, and brown sugar until glossy, thicker, and lighter in color.
• Great add-in options for these brownies are 1/2 cup (2 1/2 oz/71 g) of toasted, chopped walnuts or pecans, 1/2 cup (3 oz/85 g) of bittersweet or semi-sweet chocolate chunks or chips, 1/3 cup (1 1/2 oz/43 g) of chopped dried cherries, or 3 tablespoons of cocoa nibs.
• Be sure not to overbake these brownies: They should be set, but slightly soft in the center when taken out of the oven.
• Cut brownies when cooled: For the neatest slices, cover the cooled brownies well, and refrigerate overnight before cutting.
• Serve these brownies at room temperature or, better yet, warm with a scoop of ice cream.
• For longer storage, freeze sliced brownies on a parchment-lined baking sheet, then transfer to an airtight container, and freeze for up to two months.
  • Defrost on the counter for 30 minutes or microwave for about 10 seconds.

Make Ahead and Storage Instructions

Make-ahead tips

• You can prepare the brownie batter and store it in the fridge for up to 24 hours before baking. Just cover the bowl tightly with plastic wrap.
• If you’re feeling patient, you can store the brownie batter in the fridge for up to 72 hours. See my Fudgy 100-Hour Brownie Recipe to learn how aging batter improves flavor and texture.
• To have a brownie on hand whenever you want one, individually wrap and freeze baked brownies.
  • After cooling, freeze the brownies in a single layer on a parchment-lined tray.
  • Once frozen until firm, wrap individually and transfer to an airtight container or freezer bag for up to 8 weeks.
  • Thaw at room temperature for about an hour or microwave briefly before serving. 

How to store leftovers

• Store in an airtight container at room temperature for up to three days.
• They also freeze really well for up to eight weeks.
• After cooling, freeze in a single layer on a parchment-lined tray.
  • Once frozen until firm, transfer to an airtight container for up to eight weeks.
  • You can also wrap brownies individually and freeze.
  • Thaw at room temperature for about 1 hour or microwave briefly before serving.

FAQs

How do I make sure my brownies have a shiny, crackly top?

• The key to a shiny, crackly top is beating the eggs and sugar until they are thick, glossy, and pale.
• Check out my post, The Secret to Crinkle Top Brownies, for the science behind gorgeous shiny brownies.

Can I make these Sourdough Brownies gluten-free?

• Yes, you can make these Sourdough Brownies gluten-free.
• In place of the all-purpose flour, use an equal amount of a 1:1 gluten-free baking mix, like my Easy Almond Flour Baking Mix or another gluten-free flour.

Is it possible to make these brownies without eggs?

• Yes, you can make these brownies without eggs. Use 1/2 cup (4 oz/120 g) of full-fat Greek yogurt in place of the two whole eggs, and 2 tablespoons of full-fat Greek yogurt in place of the egg yolk.

More Brownie Recipes

• Simple Stovetop Brownies
• Butterscotch Brownies
• Vegan Brownies
• Banana Bread Brownies
• Chewy Mochi Brownies

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