Rich, and chewy with an irresistible shiny top, this Sourdough Brownie recipe is the answer to your chocolate cravings. This recipe is a great way to use sourdough discard which adds a delicious tang, making this ultimate chocolate treat even more satisfying. In less than 1 hour, you’ll have delicious brownies with just one bowl and no special equipment.
This recipe was originally published on July 2022. I have since updated it with new photos and additional tips for success.
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My perfect brownie
My perfect brownie is rich and chewy on the inside with crisp edges and a gorgeous, shiny crackly top. I’ve created a lot of sourdough discard brownies recipes over the years, like my Butterscotch Fudge Brownies from my cookbook and although these were delicious they didn’t tick all the boxes.
They never satisfied my quest for the perfect chocolate brownies because they were all missing one crucial element: the shiny, papery thin top. While I got the texture and flavor spot on, this one element that makes brownies absolutely irresistible kept eluding me. I mean what’s a good brownie without one? Just a really delicious, dense chocolate cake.
Although, I wouldn’t consider my previous attempts a complete failure, they all left me utterly dissatisfied and I didn’t touch brownies again until I figured out how to make my perfect brownies.
This recipe is INCREDIBLE. It has quickly become a staple for me when company is over, when I need to use up discard, or when I want something sweet. Everyone loves it.
- Katie
Love chocolate sourdough recipes? Try my Sourdough Chocolate Muffins, Sourdough Chocolate Cookies, Sourdough Chocolate Zucchini Muffins, Sourdough Chocolate Cake and Chocolate Sourdough Bread.
How to make brownies with a shiny, crackly crust
After hours of research (more like years tbh), reading articles by baking gurus like Tessa at Handle the Heat, PJ Hamel at King Arthur Baking Company, the indisputable team at America’s Test Kitchen, I was finally ready to make an attempt at brownies again.
Dissolve sugar properly
The crust is a result of the sugar melting and migrating to the surface of the brownies as the batter bakes, forming a delicate layer of meringue. White sugar needs to be dissolved completely in the brownie batter or you’ll end up with grainy, dull brownies. (This technique works for Sourdough Blondies as well.)
In this recipe, I microwave the sugar with butter. The hot butter helps, but because sugar dissolves in water and not fat, the little bit of moisture in butter is aided by the water locked in sourdough discard to dissolve the sugar fully.
Control the moisture in the batter
Although we need water to dissolve sugar, too much liquid will create watery brownies that can’t dry out enough to form our meringue top. This is why so many of my brownies failed in the past.
I didn’t know that the ingredients I chose added too much moisture to my batter. Dark brown sugar, espresso shots, extra egg whites, while these ingredients are harmless on their own, in combination with the water locked in sourdough discard prevented my shiny top from forming. Adding a touch of cornstarch binds even more moisture which helps with both the texture and the appearance of these brownies.
Add chocolate chips
If you’re looking for a “secret ingredient” to the perfect brownies, this is as close as you’ll get. Although a lot of recipes swear by adding chocolate chips to result in a glossy crust, the science behind it is not 100% clear. It’s thought that the soy lecithin, milk solids, and additional dissolved sugars in chocolate chips contribute to attaining that shiny, delicate top.
In her tests, PJ Hamel found that the only thing that could guarantee her crust is their addition. However, my other brownie recipes always include chocolate chips but did not have the top I wanted, so I believe that they have to be used in conjunction with the other elements I list here.
What you need
Granulated sugar - White sugar is the best choice for brownies since it doesn’t contain as much moisture as other sugars. Organic cane sugar will work for this recipe, but do not try to use brown sugar or another type of sweetener.
Sourdough discard: You can use your sourdough discard or excess sourdough starter directly from the fridge. Add 28 grams of flour and 28 grams of water into your batter if you don’t have any sourdough discard.
Cocoa powder: I used Dutch-processed cocoa powder, but natural cocoa powder will work just as well for this recipe.
All-purpose flour: Do not substitute whole wheat flour or cake flour, or it will ruin the texture of these brownies.
Cornstarch: Helps absorb excess moisture and thicken the batter, feel free to substitute another starch like potato or tapioca.
Chocolate chips: Milk chocolate or semi-sweet work best since they have more sugar. Do not use baking chocolate or chocolate bars, as it they do not contain soy lecithin. Quality matters when it comes to chocolate, so invest in
Quality matters when it comes to chocolate, when possible use high-quality cocoa powder and chocolate chips. Low-quality chocolate often contains a low percentage of cocoa solids, excessive sugar, vegetable oils instead of cocoa butter, and artificial flavors, resulting in a waxy texture and lack flavor.
See recipe card for full ingredient amounts.
Baking with sourdough discard
Sourdough discard adds a delicious tangy flavor to balance the rich flavor of these brownies. Since you’re not using it as a leavener, you can use your discard straight from the refrigerator. There’s no need to feed it or activate it before mixing it into your batter. Older discard will have a tangier, more acidic flavor than a freshly-fed sourdough starter. Both will work for this recipe, you’ll just get a slightly different flavor profile but your bake will still be delicious!
How to Make Sourdough Brownies - Step by Step
STEP 1: Melt the butter and sugar
Microwave sugar and butter together and whisk. Whisk in egg and egg yolks until the sugar looks completely dissolved. This step is pivotal for these brownies since hot butter and moisture from the egg whites and sourdough discard helps properly dissolve sugar, leading to a papery thin crackly crust.
STEP 2: Make the batter
Stir in the vegetable oil, cocoa powder. Whisk in sourdough discard until no traces remain or you may end up with gummy patches of sourdough in your brownies. Using a rubber spatula stir in the dry ingredients. Fold in the chocolate chips until evenly distributed.
STEP 3: Bake
Transfer the batter to a parchment-lined metal baking pan (8 by 8 inches). Bake the brownies at 325 F for 30 minutes. Do not over bake these brownies or they will taste chalky.
Baker's Tips
- Weigh your ingredients. Using a kitchen scale is more accurate than measuring with cups and tablespoons and will help guarantee your chances of success.
- Both active sourdough starter and sourdough discard will work for this recipe. No starter? Just add 28 grams of flour and 28 grams of water to your batter.
- Use a metal pan. Baking brownies in a metal pan result in taller, thicker and chewier brownies compared to a glass or ceramic pan.
- Don't over bake your brownies. Over baking chocolate tends to dull its flavor, so if your brownies stay in the oven too long they will taste chalky and bland.
Recipe FAQs
Absolutely! Simply use the same proportion of freshly fed sourdough starter in the recipe. Your starter won’t add a strong tangy flavor to your brownies, but it will still work.
If you don’t have a starter, but still want to try out this recipe, simply add 28 grams of all-purpose flour and 28 grams of water to your batter.
You over baked your brownies. It’s better to underbake these brownies since over baking will dull the flavor of chocolate and result in chalky, bland brownies. Only bake until the brownies are set, and until a toothpick inserted in the center comes out with a few moist crumbs attached. Don’t mistake melted chocolate chips for uncooked batter.
Brownies will keep well at room temperature stored in an airtight container for up to 3 days. Refrigerate for up to a week.
For long-term storage, wrap your brownies in foil and freeze for up to 1 month. Frozen brownie bars are what? YUM!!!
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Sourdough Brownie Recipe
Equipment
- 8 by 8 inch baking pan
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Ingredients
- 70 grams unsalted butter
- 250 grams granulated sugar
- 1 egg large
- 2 egg yolks
- 72 grams vegetable oil
- 75 grams cocoa powder Dutch-processed
- 56 grams sourdough discard
- 40 grams all-purpose flour
- ⅛ teaspoon baking soda
- 7 grams cornstarch
- 4 grams salt Morton's Kosher Salt
- 100 grams chocolate chips
- Pinch flaky sea salt optional
Click US Customary to view volume measurements
Instructions
- Prep: Preheat the oven to 325 F with the rack in the middle. Line an 8-by-8 baking pan with two pieces of parchment stacked perpendicular to each other, cut longer pieces for an overhang.
- Mix sugar and butter: Combine butter and sugar in a large mixing bowl (you’ll be using this bowl for the entire recipe so choose an appropriate size). Microwave for 2 minutes, whisk until completely combined.70 grams unsalted butter, 250 grams granulated sugar
- Whisk in eggs: Let the mixture cool slightly to prevent your eggs from heating up too much and getting scrambled. Whisk in the egg and egg yolks until the sugar appears completely dissolved.1 egg, 2 egg yolks
- Add in cocoa powder and wet ingredients: Whisk in the cocoa powder and vegetable oil. Stir in the sourdough discard thoroughly until no traces remain.72 grams vegetable oil, 75 grams cocoa powder, 56 grams sourdough discard
- Fold in dry ingredients: Add the all-purpose flour, baking soda, cornstarch and salt. Use a rubber spatula to fold the ingredients in until no dry bits remain.40 grams all-purpose flour, ⅛ teaspoon baking soda, 7 grams cornstarch, 4 grams salt
- Add chocolate chips: Stir the chocolate chips into the batter until evenly distributed.100 grams chocolate chips
- Bake: Pour the batter into your prepared pan. Bake for 30 minutes or until the brownies are set and a toothpick inserted in the center comes out with moist crumbs attached. Transfer the pan to a wire rack to cool completely before slicing.
- Enjoy and store: Sprinkle flaky sea salt on top, if using. Slice the brownies into 9 to 16 squares. Store brownies in an airtight container at room temperature for up to 3 days.Pinch flaky sea salt
Tips
These recipes were developed and tested using grams for precise measurements. To increase your chances of success, I recommend investing in a kitchen scale. I've included rough volume estimates (in tablespoons and cups), but they might not be totally accurate.
Remember all ovens are unique, these recipes were tested in my oven which runs cooler than others. You might need to lower the temperature if your bake appears to be browning too quickly. Monitor your bake closely and make adjustments if needed.
Notes
Nutrition
I am not a nutritionist or dietitian, any nutrition information provided is an estimate.
Linda says
These were, by far, the best brownies I’ve ever made! Super chocolatey! They were moist in the middle without that undercooked batter that you sometimes get. I put a rocky road topping on them and my family loved them! Will be my go to from now on! Thanks!
Hannah Dela Cruz says
This is what I love to hear! So glad your family loved the recipe.
Marion Castoire says
How delicious! This is the second time I've made it, and my daughter loves it. Since we're very careful with our sugar intake, I used Splenda, and it was delicious! This second time, we added instant coffee. OMG! Amazing! And the sourdough starter I used both times had chocolate in it. Incredible. 100% recommended! Thanks for sharing! ❤️
Hannah Dela Cruz says
So glad you loved it and the recipe worked with your substitutions.
Jewels says
WOW- the BEST brownie I have made in a very very long time. I used metric by weight in ingredients and followed the recipe as is using my discard. I baked it for 28 min instead of 30 as I really like a gooey brownie and it was perfect. My husband is in love with them! You really did get this PERFECT!!
Hannah Dela Cruz says
Thank you so much Jewels! I worked really hard to get this one right for you guys and I am so happy you're loving the recipe!
Nicole says
I've already made this recipe twice in one week. I experimented with discard I had in my fridge for 4 weeks, and everyone loved them! They didn't taste sour at all. In my oven they needed 40 minutes to bake, and I added 1 t of vanilla.
Hannah Dela Cruz says
So glad you loved it!
Sara says
Best sourdough brownies ever! We made a 1 1:2 batches and combined it all in 1 baking pan for thicker brownies
Mike Smith says
We use the version from your cookbook, very good. We live in the Philippines and have an abundance of bananas on our property. Always looking for ways to use the bananas, we sliced up a couple of cups worth and mixed into a double batch of the brownies. Came out lami kaayo.
Mike Smith
Hannah Dela Cruz says
So glad you are enjoying the book and recipes all the way in the Philippines!
Janet Moholland says
These brownies are easy to make and my daughter says they are the best brownies she has ever had. The only adjustment I make is, I add Vanilla extract and I double the batch and bake in a 9x13 pan. If you have sourdough, definitely try this recipe!
Hannah Dela Cruz says
so glad your daughter loves them!
Dani Shirey says
I have made these once before and I made them for a Super Bowl party this evening. I made a double batch, cooked them in my 9X13 cast iron baking dish, and added cinnamon chips instead of chocolate chips (we had them on hand) and these are AMAZING!!!! I also used dark chocolate instead of regular with olive oil. I love these so much because they are not overly sweet and have an amazing unique taste because of the discard. These are my go-to brownies now!
Hannah Dela Cruz says
So glad you loved the recipe, Dani! I love the changes you made and I'll have to try those myself!
Whitney says
These are currently in the oven and I am already drooling! This is my first ever sourdough recipe and even though I used rye starter, I’m still so excited to eat these! I used a mix of milk and dark chocolate chips since I don’t have a super sweet tooth and used olive oil as that was all I had. Also, can I just say how much I appreciate you listing the ingredients in each step of the recipe?? It’s a huge help not having to scroll back up to the listing. THANK YOU!! Happy I found your site and all of your amazing, thoughtfully put together recipes!
Hannah Dela Cruz says
I'm glad the recipe format helped and hope you enjoyed your brownies!
Kassidy says
Do you have a suggestion for an alternative to microwaving the sugar and butter? Would a double boiler work since we do not use the microwave to avoid the adverse health effects.
Hannah Dela Cruz says
You can melt the butter and pour it into the sugar while it is still hot.
Erica says
Overall this is a great recipe! I loved the texture! I personally have a whole wheat starter and it came out tasting a bit more sour than I’d hope. I’m wondering if the whole wheat is what brought out the sour flavor. Other than that it was great and I will definitely try again. If you have any suggestions please let me know.
Hannah Dela Cruz says
Whole wheat starters do have a tendency to be more acidic because of the presence of bran in the flour. This nutrient-dense food source encourages the growth of lactic acid bacteria which produces more lactic and acetic acid, contributing to the sour flavor and is only exacerbated by the acidity that is built up in discard that isn't regularly fed. I would try using freshly fed whole wheat starter if you want to decrease the sourness and see if that helps.
Hailey says
This worked really well! The texture was absolutely amazing. I will say- I used dark chocolate chips and the dark chocolate really does make the sour taste a little stronger from the starter. I would prob not use dark chocolate and use semi or milk chocolate to even out the bitter/sour taste. (My fault) but yes, these are great!
Hannah Dela Cruz says
Glad you loved it!