Chewy, tender with rich notes of toffee and butterscotch these Sourdough Discard Blondies are the ultimate dessert. I’ve finally perfected my blondie recipe and I’m so excited to share this recipe with you. This one-bowl recipe is made with simple pantry ingredients and a great way to use your sourdough discard.
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Sourdough Blondies Revisited
This sourdough blondie recipe was one of the first I published on this blog. Although they were good, they fell short of my desired flavors and textures, leading me to revisit and refine the recipe over three years. While achieving a rich butterscotch flavor was straightforward, attaining the desired chewy texture proved to be a persistent challenge.
In recent trials, I had the same experience that other commenters had my blondies turned out greasy, excessively gooey, and like they never fully baked. A lot of blondie recipes online are pretty straightforward, just mix all the ingredients together, bake and boom done! I didn’t see any specialized mixing or baking techniques that would help alleviate my issues. So I knew the solution to my issues would be completely redoing my recipe.
How I created my perfect blondie
After three years of continually revisiting my sourdough blondies, I finally created a recipe that works!
Decreased fat: My original recipe had 2 egg yolks and a lot more butter. While fat contributes to the desired chewiness, too much fat can’t be absorbed by the flour, leading to gummy, greasy blondies that seemingly never bake.
More mixing: Borrowing a technique from my Sourdough Brownie recipe, I adopted a more vigorous mixing technique, ensuring my sugars were completely dissolved. Similar to the brownies, this approach yielded a lighter, fluffier texture, and an added bonus—a crackly, shiny top!
Decreased the amount of sourdough discard: Too much discard introduces too much liquid in the batter, which can lead to overly crumbly blondies.
Lower oven temperature: Gently baking the blondies for an extended period ensured the blondies were baked in the center while preventing excessive browning and dryness on the surface. This adjustment effectively eliminated the risk of raw blondies with excessively crusty edges.
Looking for more sweet sourdough discard recipes? Check out my favorite Sourdough Dessert Recipes.
Why I love this recipe
- One bowl recipe that’s all mixed by hand - no stand mixer needed.
- Rich and complex flavor thanks to browned butter, brown sugar, and sourdough discard.
- Delicious chewy texture with a shiny crackly top.
What you need
Browned butter: Intensifies the nutty flavor of these blondies.
Dark brown sugar: Blondies need brown sugar to attain their rich butterscotch flavor and chewy texture. You can substitute light brown sugar but do not use granulated sugar or your blondies will be too tough.
All-purpose flour: Don’t attempt to use another type of flour to your batter, especially whole wheat flour or your blondies will become to dry and crumbly.
Sourdough discard: You can use an active sourdough starter or add 28 grams of water and 28 grams of flour to the recipe if you don’t have any discard.
See the recipe card for full ingredient amounts.
How to brown butter
- Melt the butter in a light-colored saucepan over medium heat.
- Swirl the pan occasionally or scrape the bottom with a heat-proof spatula.
- Continue heating until you notice browned spots on the bottom of your pan (thes are milk solids).
- Once your butter begins to smell nutty and appears darker, like the color of graham crackers, transfer the butter to a large mixing bowl.
Baking with Sourdough Discard
Sourdough discard adds a great tangy flavor that balances the sweet butterscotch flavor of these blondies. Since you’re not using it as a leavener, your sourdough starter does not need to be activated or fed for it to work in this recipe and you can use it straight from the refrigerator.
Older discard will impart stronger sour flavors than freshly-fed sourdough starter. Both will work for this recipe, you’ll get a slightly different flavor but your bake will still be delicious!
Looking for more creative ways to use your starter in recipes other than sourdough bread? Check out my list of sourdough recipes that aren't bread.
Variations
There are so many ways to customize these dessert bars. Here are a few delicious ideas:
- Add 2 teaspoons of espresso powder
- Use white chocolate chips or milk chocolate chips instead of dark chocolate
- Substitute pecans, peanuts or cashews for walnuts
- Add ¼ cup of shredded coconut flakes to the batter.
Step-by-step Instructions
STEP 1 Dissolve the sugars: Combine the hot melted butter and sugar, stir. The mixture will start off grainy (image 1). Add the egg in and whisk vigorously until it appears thick, smooth and satiny (image 2).
TIP: Make sure to mix the sugar into the butter first so that the mixture can cool a bit. Otherwise, your egg might end up scrambled.
STEP 2 Make the batter: Stir in your discard until fully incorporated (image 3). Fold in the dry ingredients (image 4).
TIP: You don't need to stress about too much gluten development here—plenty of fat keeps these tender. Just be sure to mix in all the dry flour, or you might end up with unbaked pockets in your blondies.
STEP 3 Bake: Stir the nuts and chocolate chips into the batter (image 5). Bake in a lined 8-inch metal pan at 325 F for 35 to 40 minutes (image 6).
TIP: Use a metal pan, it conducts heat more effectively than a glass or ceramic pan which prevents your blondies from being under baked in the center.
Baker's Tips
- Weigh your ingredients and don’t stray from the ingredients list. The key to good blondies lies in using the right ingredients in the correct proportions.
- Both active starter and sourdough discard will work in this recipe.
- Do not under bake these blondies! Just like in my Sourdough Chocolate Chip Cookies, sourdough discard has a tendency to make gooey baked goods taste raw and unappealing.
- Let the sourdough blondies cool in the pan, residual heat will allow these to bake fully while retaining their chewy texture without making them too dry.
- Don’t skip toasting your walnuts! It enhances their nutty flavor and enhances their crunchy texture.
Recipe FAQs
If you insist on gooey blondies, bake them for 28 to 30 minutes and let them cool in the pan for an hour before slicing.
Yes, but you’ll have to double the recipe, otherwise, your blondies will be too thin.
Although it’s not ideal, you can use a glass or ceramic pan in a pinch, it’s best to decrease the temperature to 315 F and add an extra 10 to 15 minutes to your baking time.
Absolutely! Wrap the sliced blondies in aluminum foil and store in a ziplock bag in the freezer for up to a month.
To reheat: Thaw the blondies at room temperature overnight. Unwrap the blondies and heat them in a 325 F oven for 5 to 10 minutes.
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Sourdough Discard Blondies Recipe
Equipment
- whisk
- 8-inch metal baking pan
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Ingredients
Batter
- 113 grams unsalted butter
- 68 grams walnuts
- 200 grams dark brown sugar
- 1 egg
- 2 teaspoons vanilla extract
- 56 grams sourdough discard
- ½ teaspoon salt
- 5 grams baking powder
- 160 grams all-purpose flour
- 78 grams dark chocolate chips
Click US Customary to view volume measurements
Instructions
- Prep: Preheat the oven to 325 F with a rack in the middle. Line an 8-inch baking pan with parchment paper.
- Brown the butter: Melt the butter in a light-colored skillet over medium heat. Swirl the pan or scrape the bottom of the pan occasionally. Continue heating until foaming subsides and the milk solids appear darker and the butter smells nutty. Move to a large mixing bowl.113 grams unsalted butter
- Toast the walnuts: Transfer walnuts to a parchment-lined baking sheet. Toast for 5 to 8 minutes or until the nuts are fragrant.68 grams walnuts
- Make the batter: Stir the sugar into the hot melted butter. Add the egg in and whisk vigorously until the mixture looks thick, smooth and satiny. Stir in the vanilla and sourdough discard until fully combined.200 grams dark brown sugar, 1 egg, 2 teaspoons vanilla extract, 56 grams sourdough discard
- Fold in the salt, baking powder and flour until no traces of dry flour remain.½ teaspoon salt, 5 grams baking powder, 160 grams all-purpose flour
- Add in the chocolate chips and walnuts.78 grams dark chocolate chips
- Bake: Transfer the batter to your prepared pan. The batter should be very thick, almost like cookie dough. Flatten the batter out to the edges of the pan.
- Bake for 35 to 40 minutes or until the center of the blondies bounce back when lightly touched and a toothpick inserted in the center comes out just a few moist crumbs.
- Let the blondies set: Set the pan on a wire rack to cool for 30 minutes before slicing.
- Enjoy and store: Slice the blondies and serve. Store leftover slices in an airtight container at room temperature for up to 4 days.
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
- Both active starter and sourdough discard will work in this recipe.
Feel free to substitute white chocolate chips or milk chocolate chips for dark chocolate. - Use peanuts, cashews, almonds or pecans in place of walnuts. Leave them out if you have a nut allergy.
- Do not underbake these blondies! Sourdough discard has a tendency to make gooey baked goods taste raw and unappealing.
- Let the blondies cool in the pan, residual heat will allow these to bake fully while retaining their chewy texture without making them too dry.
- Don’t skip toasting your walnuts! It enhances their nutty flavor and enhances their crunchy texture.
Emily P
These were really tasty but mine turned out super greasy. Like so much butter. And they took a little longer to bake too. But very good and all my friends were pleased with them!
Hannah Dela Cruz
Hi Emily - I'm so glad you still enjoyed your blondies! I was actually having the same issues with the previous iteration of this recipe so I completely reformulated it and added some useful info on the blog post about how to avoid these pitfalls. Hope you try the recipe again.
Hannah
Vera
Every time I make this, it’s so crumbly and fragile, what do you suggest ? Thank you
Make It Dough
You may be slightly over baking the blondies! Try not baking them for as long as you have.
Vera
Thank you for your reply… I was using my convection oven 170 C for 25 minutes, still confused 🤔
Make It Dough
Please keep in my mind that everyone's oven is different. Mine is not super accurate and has a tendency to run colder than others, so yours may just get a little hotter than mine does. All of these recipes are tested by me in my home kitchen, which may be different from yours so you'll have to tailor these recipes to make them work in your home. Try baking them for 18 to 20 minutes instead of 25 like you said and let us know if that works!
Carly
Every time I make these they require a lot more time in the oven and still don't seem fully cooked. What do you suggest I do to get fluffy like they look in the picture?
Make It Dough
Oh no! Sorry to hear that. You could try increasing the temperature a little bit. This bake is very forgiving! Try that and let us know how it goes.
Wendy
These are as good as you say they are. I did use butterscotch chips and added a little extra dark rum and wow! people have loved them. Thankyou!
Make It Dough
So happy you liked them!