Sponge Cake Sourdough Brownies

Name: Sponge Cake Sourdough Brownies
Prep time: 15 min
Cook time: 30 min
Total time: 45 min
Yield: 12 brownies
Ingredients: 1 cup all-purpose flour; 1/2 cup unsweetened cocoa powder; 1/2 cup granulated sugar; 1/4 cup brown sugar; 1/2 cup unsalted butter, melted; 2 large eggs; 1/2 cup sourdough starter; 1 tsp vanilla extract; 1/2 tsp salt

Highlighted under: Artisan Dessert Bakes

When I first combined sponge cake and sourdough flavors, I didn't know what to expect, but the result was a luscious dessert that quickly became a family favorite. With a delightful balance of light sponge and rich brownie texture, these brownies are perfect for any occasion. The fermentation of the sourdough adds a unique depth of flavor, making them unlike any brownie I’ve tasted before. Trust me, once you try these brownies, you’ll be hooked on their tender crumb and the subtle tang that the sourdough imparts.

Created by

Emily

Last updated on 2026-01-27T12:12:57.741Z

I was experimenting with my sourdough starter one day when I had the wild idea to mix it with a classic sponge cake recipe. The result was magical; the brownies turned out incredibly moist and had a unique flavor profile. After several trials, I found that gently folding the sourdough into the mixture right before baking was key for achieving that perfect texture.

Not only did these brownies satisfy my sweet tooth, but they also provided a newfound appreciation for the versatility of sourdough. I recommend serving them warm with a scoop of vanilla ice cream on top for an indulgent twist!

Why You'll Love These Brownies
Unique blend of sponge cake and rich brownie textures
Subtle tang from the sourdough enhances flavor complexity
Perfectly moist and goes well with ice cream

Understanding Sourdough's Role

In this recipe, the sourdough starter does more than provide a tangy flavor; it also enhances the texture of the brownies. The natural fermentation process not only tenderizes the crumb but also adds complexity that a traditional brownie lacks. The acidic nature of sourdough reacts with the baking soda present in some variations, helping to create a more pronounced lift. This means that while the final texture remains dense and fudgy, there's a lightness that elevates these brownies above standard recipes.

Using an active sourdough starter is crucial for achieving the desired effect. If your starter is too young or not bubbly, try feeding it at least a few hours before starting. This simple step ensures that your brownies will not only rise correctly but will also offer that signature depth of flavor. If you don't have sourdough starter on hand, you can substitute it with an equal amount of buttermilk or yogurt, adjusting the liquid content slightly to maintain the batter's consistency.

Tips for Achieving the Perfect Texture

One of the secrets to achieving a moisture-rich brownie lies in the butter's temperature. Allow the melted butter to cool slightly before incorporating it with the eggs and sourdough starter; this prevents the eggs from cooking and ensures a uniform mixture. When you whisk the eggs and sourdough, aim for a smooth consistency without overly aerating the mixture, which can lead to a cake-like texture instead of the dense, fudgy outcome that brownies are known for.

Pay attention to the baking time as well. Every oven is different, so start checking for doneness a few minutes before the 30-minute mark. The brownies should pull slightly away from the edges of the pan and have a set top that springs back when gently pressed. If they look undercooked, bake in increments of 2–3 minutes until you achieve the perfect baked tops. Remember, they will firm up as they cool in the pan, so don’t overbake!

Ingredients

Gather all the ingredients to prepare for baking these decadent brownies.

Brownie Ingredients

1 cup all-purpose flour
1/2 cup unsweetened cocoa powder
1/2 cup granulated sugar
1/4 cup brown sugar
1/2 cup unsalted butter, melted
2 large eggs
1/2 cup sourdough starter
1 tsp vanilla extract
1/2 tsp salt

Make sure to sift the cocoa powder and flour for a light texture.

Instructions

Follow these steps to create your Sponge Cake Sourdough Brownies.

Prepare the Oven

Preheat your oven to 350°F (175°C) and grease a 9x9 inch baking dish.

Mix Dry Ingredients

In a large bowl, whisk together the flour, cocoa powder, granulated sugar, brown sugar, and salt.

Combine Wet Ingredients

In a separate bowl, mix the melted butter, eggs, sourdough starter, and vanilla extract until smooth.

Combine Mixtures

Pour the wet mixture into the dry ingredients and stir until just combined. Avoid overmixing.

Bake the Brownies

Pour the brownie batter into the prepared baking dish and spread evenly. Bake for 30 minutes or until a toothpick comes out clean.

Cool and Serve

Let the brownies cool in the pan for at least 15 minutes before cutting into squares.

Enjoy your delicious brownies warm or at room temperature.

Pro Tips

For an extra touch, add chocolate chips or nuts to the brownie batter before baking.

Storing Your Brownies

Once your brownies have cooled completely, store them in an airtight container at room temperature for up to three days. If you want to extend their freshness, consider wrapping them tightly in plastic wrap and placing them in the refrigerator. This will help maintain their moisture while also allowing the flavors to deepen. Just remember, brownies tend to taste best when served at room temperature — so pop them out for about 15-20 minutes before serving.

For longer storage, you can freeze brownies for up to three months. Cut the brownies into squares, then wrap each piece in plastic wrap followed by aluminum foil to prevent freezer burn. When you're ready to enjoy them, simply thaw at room temperature or warm gently in the microwave for a few seconds for a fresh-baked texture.

Serving Suggestions

Consider serving these brownies with a scoop of vanilla or chocolate ice cream for a delightful contrast of temperatures and textures. The cold ice cream melts slightly into the warm brownie, creating a rich dessert experience. You can also top with a drizzle of chocolate or caramel sauce for an extra indulgent treat. A sprinkle of sea salt can bring out the chocolate flavors even more, elevating the entire dessert.

If you're looking to add a festive touch, try dusting the brownies with powdered sugar or serving them with fresh berries like raspberries or strawberries. The acidity in the berries complements the sweetness of the brownies and adds a beautiful pop of color. Feel free to get creative — adding nuts or a layer of chocolate ganache could take this recipe to new heights!

Questions About Recipes

→ Can I use whole wheat flour instead of all-purpose flour?

Yes, whole wheat flour can be used, but it may alter the texture slightly and make the brownies denser.

→ How should I store leftover brownies?

Store any leftovers in an airtight container at room temperature for up to 3 days or refrigerate for longer freshness.

→ Can I freeze these brownies?

Absolutely! Freezing is a great way to preserve them. Wrap the brownies tightly in plastic wrap and then place them in an airtight container for up to 3 months.

→ Can I use store-bought sourdough starter?

Yes, store-bought sourdough starter works just fine. Just make sure it's active before using.