Sourdough brownies have a rich chocolate flavor, fudgy texture, and a signature sourdough kick. Whip them up in an afternoon or long ferment them overnight.

This sourdough brownie recipe is one of my favorite ways to utilize sourdough starter discard. (See some of my other sourdough discard recipes in this post.)
When chocolate cravings hit, it is usually sourdough chocolate cake, fresh milled chocolate chip cookies, sourdough chocolate rolls, or these brownies that find their way to my oven.
If you are used to grabbing a box mix for brownies, you have to give this a try. These easy sourdough brownies are so simple and do not require an extra trip to the grocery store. Everything in the recipe is likely in your fridge or pantry already.
Serve with a cold glass of milk, a dollop of whipped cream, or a scoop of homemade vanilla ice cream for the perfect treat.
Why You’ll Love This Recipe
Delicious – Gooey centers with a crackly top, these are classic brownies with a burst of sourdough flavor.
Long Fermented (optional) – Long ferment this recipe it to help break down the phytic acid, reduce the gluten content, and make the nutrients more bioavailable.
Great way to use discard – If you have a brand new starter, this is a great recipe to use up the discard.
Ingredients

Butter – Use unsalted butter to control the amount of salt in the recipe. You can also use a neutral oil, like avocado oil.
Semi-sweet chocolate chips – This gives it a nice balance without making the brownies too sweet.
Vanilla – I use homemade vanilla extract.
Flour – Whole wheat flour, spelt, or all purpose flour will work. You can also check out my brownie recipe using freshly milled flour.
A full ingredient list with exact amounts can be found in the recipe card below.
How To Make Sourdough Brownies

Step 1: Preheat the oven to 350 degrees Fahrenheit and prepare a 9″ × 9″ pan by lining it with parchment paper. In a medium saucepan over low/medium heat, melt butter. Take off heat and add chocolate chips and vanilla.

Step 2: Stir until all melted together.

Step 3: In a medium or large bowl, combine flour, sugar, cocoa powder, and salt. Stir to combine.

Step 4: Pour melted chocolate mixture into the dry ingredients. Add in eggs and sourdough discard. Stir well until there are no clumps.

Step 5: Pour the sourdough brownie batter into prepared pan.

Step 6: Bake for 40 minutes in the prepared 9″ x 9″ pan or until a toothpick comes out clean and the middle is set. Allow to cool completely before slicing and serving. This will help it set up and also develop the flavors.
Tips
- My sourdough starter is at 100% hydration, meaning I feed it with equal parts flour and water.
- Make sure your eggs are room temperature. If you forgot to take your eggs out of the fridge ahead of time, you can bring them up to room temperature by placing them in a bowl of hot water for 5 to10 minutes.
- Allow the brownies to cool totally before cutting. Once they are completely cooled, the flavor will have developed, and the brownies will hold together.
- Long ferment the dough overnight to add more delicious tang from the fermentation of the grains. Combine the flour, sourdough starter, sugar, and half a cup of melted butter the night before. Cover and leave overnight or up to 24 hours. The next day, add the rest of the ingredients.
Recipe FAQ’s
Basically sourdough adds flavor. If you have excess sourdough starter, this is an easy recipe to try! If you long ferment the recipe overnight, you will gain the benefit of easier digestion thanks to the breakdown of phytic acid.
If these are made without long fermenting, then they are basically the same as regular brownies. If long fermented, sourdough helps to make the gluten in the brownies easier to digest.
Fudgy brownies have more fat in them than flour, while cake like brownies have more flour than fat.
Store in an airtight container for up to 2 or 3 days at room temperature or in the fridge for 3 to 5 days. These also freeze well! Freeze for up to three months once completely cooled.
More Sourdough Dessert Recipes
- Sourdough Chocolate Chip Cookies
- Sourdough Monster Cookies
- Sourdough Monkey Bread
- Sourdough Discard Double Chocolate Bread
- Sourdough Discard Blondies
If you try this recipe and love it, I would love it if you could come back and give it 5 stars! Tag me on Instagram @farmhouseonboone.















Thanks, my husband said it was the best brownies that I have made.
When long fermenting, are you mixing only the flour, melted butter, sourdough discard and sugar? Adding the rest in the morning before baking?
Yes, correct.
Perfect middle and perfect crust.
Hi, I noticed you can no longer double, triple etc the recipes on your website. Are you able to add that feature back in by any chance? I found it very helpful. Thank you for sharing all your wonderful recipes and tricks!
I wish I could! The doubling button was significantly impacting the conversion between volume and metric measurements. It was causing a lot of issues for anyone using metric measurements, so I had to remove the feature.
When you look at the brownie recipe in your book, you say to brown the walnuts but don’t say when to add them. Then you say to mix until it is smooth. But with the nuts how can it be smooth? Beautiful book by the way. I also bought one for my son.
Add them after mixing the batter together.
Delicious! I used half a cup fresh milled flour for the flour and only 3/4th cup sugar. Was perfect.
“BEST brownies I’ve ever had” says my husband. Try these…you won’t be sorry.
How long would you bake these brownies if you double it and bake in a 13×9 pan?