Fudgy Brown Butter Sourdough Brownies

After multiple rounds of testing, I finally created my perfect brownie! They're super fudgy and chocolatey with a slight nuttiness from the brown butter, hint of cinnamon and extra depth of flavor from sourdough discard. I have no doubt that you are going to absolutely love these brownies too.

The mix of melted chocolate and dutch process cocoa create the most rich, luxurious brownies. I just can't wait for you to give these a try!

If you love brownies and want even more brownie recipes to enjoy, try these Peanut Butter S'more Brownies, my classic Chewy Fudgy Brownies and my Fudgy Peppermint Mocha Brownies for a festive holiday treat.

Why you'll love my sourdough brownie recipe

• Sourdough Discard. This recipe uses sourdough discard in the batter to really elevate the flavors and give the brownies a very subtle tangy, but delicious, flavor that you won't get from any other brownie recipe! It also helps to tenderize the gluten, creating incredibly soft, melt in your mouth brownies. It's a great way to use up excess discard so that it doesn't go to waste. It's a win-win!
• Incredible texture and flavor. They are chewy, rich and so fudgy. The browned butter incorporated into the recipe really helps boost all the flavors. The combination of melted chocolate, Dutch process powder with hints of of espresso and cinnamon to really intensify the chocolate flavor and add depth to the recipe.
• Perfect little treat. This is an excellent dessert to enjoy anytime. Brownies are just the right size to delight in without the guilt. If you are a chocolate lover these are for you! 

What is sourdough discard

Sourdough discard is the portion of the sourdough starter that is removed and "discarded" before feeding the remaining starter. Instead of tossing your discard in the trash, you can use it bake delicious desserts like brownies!

I like to keep a discard jar in the fridge that I continually add to. Overtime, you will collect quite a bit of discard. It's a good idea to label the jar and swap it out every month or so.

What is brown butter?

Brown butter is made my heating butter until the milk solids caramelize, giving the butter a golden color and a rich, nutty, almost caramel like flavor. It's addicting in baked goods!

Ingredients + Notes

Scroll down to the recipe card for full ingredient lists with measurements.

• Butter. I use salted butter in all my baking recipes.
• Cocoa powder. This recipe was made with Dutch process cocoa powder, and I highly recommend you use it instead of natural cocoa powder. Dutch process cocoa is less acidic and, therefore, pairs better with sourdough discard. The acidity in regular cocoa powder can add a subtle tanginess since there's no baking soda in the recipe to neutralize it, and since sourdough discard is already a bit tangy, it's best to use Dutch processed cocoa. If you do use natural cocoa powder the brownies will still turn out great, but they will be a bit more tangy!
• Instant expresso powder. Instant espresso powder helps intensify the chocolate flavor in the brownies. Don't worry, your brownies won't taste like coffee. But if you don't have any on hand, that's ok too!
• Cinnamon. Oh my gosh cinnamon is my new secret weapon when it comes to chocolate desserts! It's just a small amount of cinnamon to add just a hint of flavor. It compliments the chocolate so well! I also like to add cinnamon to my insanely delicious Chocolate Glazed Brownie Donuts.
• Chocolate. Dark or semi-sweet chocolate can be used. I typically use a good quality chocolate bar such as Lindt or Ghirardelli, but you can use chocolate chips if you prefer!
• Eggs. Just the right amount of eggs to create fudgy, but not cakey, brownies.
• Sugar. This recipe calls for brown and white granulated sugar. Both are very important to use. The brown adds moisture and gives the brownies that soft and fudgy texture. The white creates chewiness and helps to form that thin crinkly top.
• All purpose flour. This is the only flour used and recommended for this recipe. Please don't substitute with cake flour or whole wheat.
• Sourdough discard. You can use fresh discard or one that has been refrigerated. It just needs to be 100% hydrated. Older discard will add a little more tang than newer discard.
• Vanilla extract.
• Salt

How to make sourdough brownies

Scroll down to recipe card for full instructions.

• Step 1: Brown the butter. Melt the butter making sure to stir frequently. Continue stirring until it turns golden brown. Remove from heat. Browning butter gives the brownies an extra depth of nutty flavor and richness. It truly is the secret to amazing brownies.
• Step 2: Add powders and chocolate. Whisk in the cocoa, espresso powder, cinnamon and chocolate until melted.
• Step 3: Create the perfect crinkly top. Using a standing mixer, bring eggs, sugars, and vanilla together. Make sure you beat until fluffy and lighter in color. It will have a foamy texture like meringue. You want to make sure the sugars are fully dissolved in the mixture. This will help with forming the top crust.
• Step 4: Combine ingredients. Bring the warm chocolate mixture, eggs and sugar mixture together then add in the discard. Beat on low until just combined.
• Step 5: Add flour and salt. Fold in the flour and salt until they are just combined. We don't want to over combine, or it will change the consistency of the brownies.
• Step 6: Bake. Pour the batter into a prepared baking dish and bake. Metal baking dish is going to be the best option for baking brownies versus glass. See the FAQ section to learn why.

Frequently asked questions

What is the grey liquid on my sourdough starter?

Your sourdough starter or discard jar may have a grayish liquid on the top, which is called hooch. Hooch is an indication that your starter is hungry. Hooch develops when your starter has eaten through all of its food (flour and water). You can mix the hooch in or pour it off. Mixing the hooch in will give your starter or discard a more tangy sourdough flavor.

Why discard sourdough starter?

In order to maintain a good, healthy, active starter, you must feed it with flour and water on a regular basis (either daily or weekly if kept in the fridge). If you don't discard starter before feeding again, you will end with a never ending oversupply of starter that you won't be able to keep up with.

What is Dutch process cocoa?

Dutch process cocoa is growing in popularity in the United States. It's Natural unsweetened cocoa that has been treated with an alkalizing agent to lessen its acidity. This is especially important when baking brownies because brownies don't call for any baking soda, which neutralizes the acidity in natural cocoa powder. Click here for a great article written by King Arthur Baking on the difference between Dutch process cocoa and natural cocoa.

Can I make these sourdough brownies with natural cocoa powder?

You can make sourdough brownies with natural cocoa powder, but Dutch process offers a better chocolate flavor and helps to lessen the tangy flavor.

How do I make sure I get a shiny crinkly top to my brownies?

The most important thing you can do is make sure the sugar dissolves into the eggs. This is achieved by beating the sugar and eggs until fluffy. You will want a foamy texture that creates a meringue like consistency.

Why is it important to bake brownies with a metal pan instead of a glass pan?

Metal and glass pans transfer heat differently. Glass transfers heat more slowly than metal. This can result in a shorter brownie with overcooked edges. Metal pans transfer faster resulting in a taller, thicker, chewier and more fudgy brownie. If you use glass, you may need to add more cook time.

How do I know when the brownies are done?

The brownies will look set around the edges and have nice crinkly crust forming over the top. Check for doneness by inserting a toothpick into the center of the brownies starting at 35 minutes. The toothpick should come out with moist crumbs, but not wet batter. The brownies will continue to cook and firm up from residual heat out of the oven, which is why it's important to let them cool completely before slicing.

Tips for the Best Sourdough Brownies

• Make sure to beat the eggs and sugar for 6-8 minutes. The mixture should be light and foamy looking, like meringue. This helps to create that beautiful thin crinkly top that we all love.
• Use a standing mixer or electric hand mixer. To create those perfect brownie tops, it is best to use either of these mixers. If you don't have either, you can just use a whisk. The brownies will still be delicious, you just may not have that same crinkly top.
• Use Dutch processed cocoa. Natural cocoa powder, such as Hershey's, will add a bit more tang and bitterness to the brownies. Dutch process gives you a richer and better chocolate flavor.
• Use a metal baking pan. Heat transfers differently between metal and glass pans. For brownies, it is best to use a metal pan because this allows for faster baking. It also plays a huge role in the height of the brownies and the texture.
• Don't overmix the flour. You don't want to overmix the flour into the batter. This can result in a dense brownie. I like to use a rubber spatula to help fold the flour in until gently combined.
• Don't overbake the brownies. You don't want to overbake them, or they will become a bit dry and crumbly. I like to take them out when after inserting a toothpick, it comes back with a few moist crumbs. We don't want a wet batter, but we also don't want a dry brownie either.

Storing brownies

• Storing. Store brownies it in an airtight container or resealable bag at room temperature for up to 4 days, or in the refrigerator for up to 1 week. If I'm pulling a brownie from the fridge, I like to pop it in the microwave for 10-15 seconds before eating it so it's warm and gooey.
• Freezing. Brownies freeze very well. Wrap individual brownies in plastic wrap then place in a freezer safe container or bag for up to 1 month. Thaw in the fridge or on the counter.