Sourdough Brownies with Marshmallows

Name: Sourdough Brownies with Marshmallows
Prep time: 15 min
Cook time: 25 min
Total time: 40 min
Yield: 12 brownies
Ingredients: 1 cup unsweetened cocoa powder; 1 cup all-purpose flour; 1/2 teaspoon baking powder; 1/4 teaspoon salt; 1 cup granulated sugar; 1/2 cup unsalted butter, melted; 2 large eggs; 1 teaspoon vanilla extract; 1 cup sourdough starter (discard or active); 1 cup mini marshmallows

Highlighted under: Sweet Treat Creations

I love creating new twists on classic desserts, and these Sourdough Brownies with Marshmallows are a perfect example of that! The earthy tang of sourdough balances beautifully with the rich chocolate flavor, while the marshmallows add a delightful chewy texture. The first time I made these, I was pleasantly surprised by how much the sourdough energized the brownies. They turned out decadently fudgy and incredibly satisfying. This recipe showcases how a staple like sourdough can elevate even the most beloved treats into something extraordinary.

Created by

Olivia

Last updated on 2026-01-27T14:34:28.819Z

As I embarked on baking these Sourdough Brownies, I was intrigued by the unique flavor profile that would come from incorporating sourdough. The first bite brought a satisfying tang that perfectly complements the rich chocolate. I especially enjoyed the surprise bursts of melted marshmallow that created a perfect contrast in texture.

In my experience, allowing the brownies to cool slightly before cutting into them makes a significant difference. It helps the brownies set and makes for cleaner slices, which is always a plus when serving.

Why You'll Love This Recipe
Decadent chocolate flavor with a hint of sourdough tang
Soft, chewy texture with gooey marshmallow pockets
A unique twist that will impress friends and family

The Role of Sourdough

Sourdough starter is not just an ingredient; it's a game changer in these brownies. The natural fermentation process adds a depth of flavor that enhances the chocolate without being overpowering. The subtle tang balances the sweetness, making every bite a complex experience. Plus, using sourdough starter means you can utilize that leftover discard which often goes to waste, giving your baked goods a second chance at life.

In addition to flavor, the acidity in the sourdough actually helps to tenderize the brownies. It reacts with the cocoa powder and brings out a deeper chocolate flavor while contributing to a moist texture. If you're using active starter, keep in mind that it may add a slightly different rise to the brownies, yielding an even airier crumb, perfect for those who love lighter, fluffier desserts.

Choosing the Right Marshmallows

The choice of marshmallows can significantly affect the final texture of your brownies. Mini marshmallows melt perfectly, creating delightful gooey pockets throughout the fudgy base. It's best to use high-quality, fresh marshmallows to ensure they melt well without becoming rubbery. If you prefer a different approach, try using large marshmallows cut into quarters for bigger bites of chewiness.

For those looking for a dietary swap, consider using vegan marshmallows, which are widely available. They will still provide that sought-after gooeyness without compromising on flavors. Just be aware they might not caramelize as well under heat, but they do offer a similar chewy delight that fits into a plant-based diet.

Storage Tips and Variations

Once you've baked and cooled your brownies, store them in an airtight container at room temperature for up to five days. For longer storage, consider freezing them. Simply wrap individual brownies tightly in plastic wrap and then place them in a freezer-safe bag. They can last for up to three months in the freezer; just allow them to thaw at room temperature for an hour before enjoying.

Want to change things up? You can easily customize this recipe by adding nuts like walnuts or pecans for added crunch or integrating chocolate chips for double chocolate goodness. Spice lovers might try adding a pinch of cinnamon or even a bit of espresso powder to elevate that chocolate flavor even further. The possibilities are endless with this versatile recipe!

Ingredients

Brownie Base

1 cup unsweetened cocoa powder
1 cup all-purpose flour
1/2 teaspoon baking powder
1/4 teaspoon salt
1 cup granulated sugar
1/2 cup unsalted butter, melted
2 large eggs
1 teaspoon vanilla extract
1 cup sourdough starter (discard or active)
1 cup mini marshmallows

These ingredients come together to create a rich, flavorful brownie that you can’t resist!

Instructions

Prepare the Oven

Preheat your oven to 350°F (175°C) and line a square baking pan with parchment paper.

Mix the Dry Ingredients

In a medium bowl, whisk together cocoa powder, flour, baking powder, and salt until well combined.

Combine Wet Ingredients

In a large bowl, mix melted butter and sugar until smooth, then add the eggs one at a time, mixing in between. Stir in vanilla and sourdough starter until integrated.

Incorporate Dry Ingredients

Gradually add the dry mixture to the wet ingredients, mixing until just combined. Be careful not to overmix!

Add Marshmallows and Bake

Fold in the mini marshmallows gently. Pour the batter into the prepared pan and bake for 25 minutes or until a toothpick comes out mostly clean.

Cool and Slice

Let the brownies cool in the pan for about 10 minutes before lifting them out using the parchment paper. Allow them to cool completely before slicing into squares.

Enjoy your delicious Sourdough Brownies with Marshmallows!

Pro Tips

For an extra indulgent touch, serve these brownies warm with a scoop of vanilla ice cream on top.

Baking Tips for Perfect Brownies

To ensure your brownies come out perfectly every time, avoid overmixing the batter once you've combined the dry and wet ingredients. This is key for achieving that desired fudgy texture. Mix until just combined; a few streaks of flour are acceptable as they will incorporate during baking.

Pay attention to the baking time as well; every oven is different. Check your brownies at the 20-minute mark. You want a toothpick inserted in the center to come out with a few moist crumbs, not completely clean. This will ensure that your brownies retain their fudgy nature.

Serving Suggestions

For a delightful serving idea, warm up your brownies for a few seconds in the microwave before serving, and top with a scoop of vanilla ice cream. The contrast of warm brownie and cold ice cream creates an unforgettable dessert experience. Drizzle with chocolate sauce or a sprinkle of sea salt for an extra touch that's sure to impress.

If you're serving these brownies as part of a larger dessert table, consider pairing them with fresh strawberries or raspberries. The tartness of the berries cuts through the richness of the brownies beautifully, adding a fresh element that balances the flavors perfectly.

Questions About Recipes

→ Can I use active sourdough starter?

Yes, both active or discard sourdough starter work well in this recipe.

→ What can I substitute for the butter?

You can use an equal amount of coconut oil or a vegan butter substitute.

→ How do I store leftovers?

Store them in an airtight container at room temperature for up to 3 days or refrigerate for up to a week.

→ Can I add nuts to the brownies?

Absolutely! Chopped nuts such as walnuts or pecans can be delicious additions.