If you have a sourdough starter and are looking for great recipes to use the sourdough discard, these Sourdough Discard Brownies should be on your list! These brownies are fudgy, not overly sweet, and you really taste the sourdough flavor come through. If you're looking for a delicious brownie with a more complex sourdough flavor, this one is for you!
When I'm working with sourdough discard, I like to make recipes that use up a lot of it. If you've ever fed a sourdough starter, you know you have a lot of discard to go through, and it's such a shame to waste it! This recipe (along with all my other sourdough discard recipes) uses 1 cup of unfed, room-temperature sourdough discard.
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As long as you have sourdough discard, you are well on your way! In general, brownies are a simple recipe, but the ingredients you use make a big difference. You'll need a few key ingredients to pull these Sourdough Discard Brownies together.
- Eggs: This recipe uses two eggs, which should be at room temperature when you beat them. Using room-temperature eggs (rather than right out of the fridge) helps the sugar dissolve more easily.
- Granulated sugar: Combining the sugars with the eggs is one of the most important steps of this recipe. If you have superfine baking sugar (or caster sugar), this is also great to use here.
- Brown sugar: I like to use light brown sugar, but if you want a deeper flavor, you can use dark brown sugar.
- Dark chocolate chips: These chocolate chips will be melted, so there will not be any chips in the brownies. I like to use dark chocolate chips (these Guittard Extra Dark Chocolate Chips are my favorite), but if you prefer, you could use milk chocolate chips.
- Sourdough discard: The sourdough discard should be unfed and at room temperature for this recipe. See the section below on working with sourdough discard.
- Unsweetened cocoa powder: I like to use Hershey's Unsweetened Cocoa Powder, but you could also use Special Dark or Dutch Processed Cocoa Powder, you can, but note that the brownies will have a slightly different flavor profile.
- Flaky sea salt: This is optional, but I highly recommend sprinkling some flaky sea salt on the batter before it bakes. I love to use Maldon Sea Salt for their extra-large flakes!
See full recipe below for detailed directions.
There are only a few steps to making Sourdough Discard Brownies, but there are a few important moments. Take your time and make sure to follow all directions.
In a small saucepan over medium-low heat, combine butter and dark chocolate chips. Stir until fully melted, then set aside to cool.
In the bowl of a stand mixer fitted with a whisk attachment, begin beating the eggs. With the mixer running, slowly add the sugars, then the vanilla and water. Increase speed to medium-high and whip the mixture until the sugars have completely dissolved, about 8-10 minutes.
Combine the butter-chocolate mixture with the sourdough discard and stir until combined.
Using a spatula, gently fold the butter-chocolate mixture and the cocoa powder into the whipped eggs. Mix until just combined and no dry spots remain. The batter will be light and fluffy.
Pour the batter into a greased 8x8-inch baking pan lined with parchment paper.
Sprinkle with flaky sea salt, then bake.
Once you remove the brownies from the oven, let them sit in the pan for at least 20 minutes. The brownies will continue to bake as they sit in the pan, so don't skip this step! Remove them from the pan and cut the slab of brownies into 16 squares before serving.
Hint: Everyone likes their brownies in a slightly different way. If you're looking for fudgy brownies, bake on the lower end of the suggested time. If you're looking for more cakey brownies, bake on the longer end of the suggested time.
Whipping the eggs and sugar
Mixing together the eggs and sugar is one of the most important parts of this recipe. Using a stand mixer, you'll likely need to whip the mixture for about 8-10 minutes until the sugar is completely dissolved. Touch the mixture and rub it between two fingers to see if you can still feel the sugar crystals. If you can, then keep mixing!
This process of whipping the eggs and sugar together until thick is also called mixing it to the "ribbon stage." When finished, the mixture will be light and fluffy, and will fall from the whisk in a "ribbon" before reincorporating fully.
How to tell when brownies are done
It can be hard to tell when brownies are done baking, especially if you're looking for fudgy brownies. Remember that when you remove the brownies from the oven, you're going to let them sit in the pan for an additional 20 minutes. The brownies will continue to firm up during this time!
When you take the brownies out of the oven, the top should look set and the edges firmed. If the center still looks visibly wet, you need to bake them longer. You can also test with a toothpick in the center of the tray:
- For fudgy brownies: Insert a toothpick in the center of the tray. It shouldn't be completely covered in wet batter, but it will still have some batter chunks stuck to it.
- For cakey brownies: Insert a toothpick in the center of the tray. The brownies are done when the toothpick comes out clean or nearly clean.
If you try the toothpick test and it's coming out completely covered in wet batter, those brownies are undercooked. Continue baking for a few more minutes.
Working with sourdough discard
This recipe is designed to be made from a sourdough starter with a 1:1:1 ratio (when you feed the starter, it's with 1 part starter, 1 part flour, 1 part water). If your sourdough starter uses a different ratio, you may need to adjust the ingredients slightly if the batter feels too wet or too dry.
There isn't typically yeast in brownies, so the sourdough here does add some additional lift, as well as sourdough flavor. This recipe doesn't use any extra flour outside of the sourdough discard.
There are a few substitutions you could make to adapt these brownies slightly:
- Use active sourdough starter - If you want to, you could try this recipe with active sourdough starter instead of sourdough discard. This will lend itself towards a more cakey brownie with additional lift.
- Use different chocolate - This recipe uses dark chocolate, but it could also be made with milk chocolate for a different flavor.
I highly recommend using a stand mixer to whip the eggs and sugar (I use a KitchenAid 5-Quart Stand Mixer). This can be done with a hand-held mixer, but just know that you'll be mixing for 10+ minutes, and that can be a really long time when you're doing the work! Use a kitchen scale to measure the sourdough discard.
You'll need a small saucepan to melt the butter and chocolate, as well as a few spatulas for mixing and an 8x8-inch baking pan. I like to spray the pan with cooking spray and line it with parchment paper - I find that makes it easier to take the brownies out of the pan.
If you're in a pinch, you can use a larger or smaller baking pan, but keep in mind that will change the baking time that is needed.
These Sourdough Discard Brownies can be stored in an airtight container at room temperature for 3-4 days. The longer they sit, the more they will dry out.
Brownies can also be frozen in an airtight container for up to 3 months. You can freeze them in an entire slab, or in cut squares. If you're freezing the cut squares, make sure to put a piece of parchment paper between each square to prevent them from sticking to each other. Let the brownies thaw to room temperature before serving.
While it's important to mix the eggs and sugar long enough, it's also important not to mix the batter for too long. Spend time whipping the eggs, then when you combine the egg mixture, butter mixture, and cocoa powder, switch to using a spatula and gently fold the ingredients together. Fold until just combined and no dry spots remain. The batter will feel very light and fluffy. If you overmix the batter at this stage, the brownies will be much more dense.
This recipe is designed to be made with sourdough discard, but would also work with active sourdough starter (for a more cakey brownie).
The top of the brownies should look visibly set and the edges firmed. Use a toothpick inserted in the center to judge how set the center of the batter is. For fudgy brownies, you want the toothpick to come out with some batter still clinging to it (not completely wet with batter). For cakey brownies, you want the toothpick to come out with almost no batter sticking to it.
After removing the brownies from the oven, they'll rest in the pan for at least 20 minutes. During this time, the brownies are still baking and firming up. If they feel a bit under-cooked when you take them out of the oven, remember that you still have this additional time where they'll continue to firm!
Sourdough Discard Brownies
- 10 Tablespoons unsalted butter
- ½ cup dark chocolate chips
- 2 eggs room temperature
- ½ cup granulated sugar
- ½ cup brown sugar
- 2 Tablespoons water
- 2 teaspoons vanilla extract
- ½ teaspoon kosher salt
- 200 grams (about ¾ cup) sourdough discard unfed, at room temperature
- ¾ cup unsweetened cocoa powder
- flaky sea salt, for topping optional
- Preheat oven to 350℉. Line an 8x8-inch baking pan with parchment paper and spray with cooking spray. Set aside.
- In a small saucepan over medium-low heat, heat the butter and chocolate chips. Stir until completely melted and smooth. Set aside to cool.
- In the bowl of a stand mixer* fitted with a whisk attachment, add eggs and turn mixer to low. With the mixer running, slowly pour in the granulated sugar and brown sugar. Add 2 Tablespoons water. Increase speed to medium-high and mix until the sugar has completely dissolved, about 8-10 minutes. Rub some of the mixture between your fingers; if you can feel sugar granules, then keep mixing. When ready, the mixture will be light in color and fluffy. Add vanilla extract and salt.
- Mix together the sourdough discard and the chocolate butter mixture in a medium bowl. Use a whisk to combine, if needed.
- Add the sourdough discard mixture and the cocoa powder to the egg mixture. Use a spatula to gently fold, mixing until just combined and no dry spots remain (don't overmix the batter!).
- Pour the batter into the prepared pan and sprinkle with flaky sea salt (optional). Bake for 30-35 minutes**. The top should look set and the edges firmed. Remove from the oven and let the brownies sit in the pan for at least 20 minutes (they will continue to firm up during this time).
- Remove from the pan and let cool fully. Slice into 16 pieces before serving.