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sourdough blondies

Sourdough Blondies Recipe


Yield: 16 bars
Prep Time: 10 minutes
Cook Time: 35 minutes
Total Time: 45 minutes

These are the best Sourdough Blondies ever! Chewy, buttery sourdough blondies with chocolate chips made with sourdough discard and baked into soft squares. A low-fuss but highly delicious quick sweet treat!

5 from 2 votes

Ingredients

  • 245 grams all-purpose flour 1 3/4 cup
  • 2 grams baking powder 1/2 teaspoon
  • 3 grams fine sea salt 1/2 teaspoon
  • 170 grams unsalted butter, melted 12 Tablespoon
  • 210 grams light brown sugar, packed 1 cup
  • 100 grams sugar 1/2 cup
  • 100 grams sourdough discard 1/3 cup
  • 1 large egg room temperature
  • 1 egg yolk room temperature
  • 8 grams pure vanilla extract 2 teaspoons
  • 200 grams 1 cup chocolate chips, divided 1 cup

Instructions

  1. For an even more flavorful Sourdough Blondies, I highly recommend browning your butter before adding it to this recipe! It brings a delicious nutty flavor that goes perfectly with the chocolate chips. See Notes below on how to brown butter.
  2. Preheat the oven to 350 degrees F and grease an 8x8 baking dish or line with parchment paper. Set aside.
  3. In a medium bowl, whisk together the flour, baking powder and salt. Set aside.
    245 grams all-purpose flour, 2 grams baking powder, 3 grams fine sea salt
  4. In a large bowl, add the melted butter, sugars, sourdough discard, egg + egg yolk, and vanilla. Whisk until smooth.
    170 grams unsalted butter, melted, 210 grams light brown sugar, packed, 100 grams sugar, 100 grams sourdough discard, 1 large egg, 8 grams pure vanilla extract, 1 egg yolk
  5. Using a rubber spatula, gradually add and fold the flour mixture into the wet ingredients. When there are just a few streaks of flour remaining, pour in the chocolate chips, or other desired mix-ins, and fold until everything is combined.
    Feel free to include or substitute the chocolate chips for other options like chopped pecans or walnuts, or white chocolate, dark, maple chips, etc.
    200 grams 1 cup chocolate chips, divided
  6. Evenly spread the thick batter into the prepared baking dish. Top with more chocolate chips, if desired.
  7. Bake for 35-40 minutes or until the edges are just golden brown and the center is still soft. Be careful not to overbake.
  8. Cool completely before slicing and serving. Slice into 8 large or 16 small slices and enjoy!

Notes

How to Make Browned Butter

Melt 226 grams (1 cup) of unsalted butter in a medium-sized frying pan over medium heat, stirring occasionally. Once the butter is fully melted, it will begin to bubble. Continue to stir constantly until the bottom of the pan is covered with small amber specks (about 2–3 minutes). You should be left with 170g of browned butter.
Carefully remove the browned butter from the heat and pour it into a large mixing bowl. Allow the butter to come to room temperature for at least 20-30 minutes.

Ingredients & Substitutions

  • Flour – I used all-purpose flour for these sourdough blondies. If you are not using a kitchen scale, be sure to fluff and then scoop your flour into your measuring cup. If you want a perfectly chewy blondie, don't add too much flour because it makes it turn out thick and kind of cakey.
  • Baking Powder – Gives just enough lift to the blondies! Be sure to check the expiration date and replace your leaveners every 6 months, otherwise the cookies won’t rise properly.
  • Sugars – I used a combination of light brown sugar and white sugar. Dark brown sugar could also work, offering the classic flavors of brown sugar, though I haven’t tested it in this recipe.
  • Butter – For an extra nutty flavor, add browned butter instead of melted butter! Melt 226 grams (2 sticks) of unsalted butter and brown until left with 170 grams of browned butter. Allow the butter to cool for at least 30 minutes before adding to the wet ingredients. There’s no perfect gooey blondie without butter.
  • Sourdough Discard – For blondie recipes and other sweeter recipes, I prefer to use fresh sourdough discard (room temperature), no older than 2 days. You can also use active sourdough starter. For the best results, be sure to use the same amount in grams.
  • Mix-ins – I kept these blondies super simple and just added semi-sweet chocolate chips, but this is where you can let your creativity wild! From white, butterscotch or maple chips, to adding in some chopped pecans, walnuts, pistachios, or whatever you like. 
  • Salt – Helps balance the sweetness and brings out all the flavors in the batter. Any unrefined salt will work here, but I like using Redmond’s unrefined salt for those extra minerals.
  • Egg – Adds structure and richness to the blondies.
  • Egg Yolk – Egg yolks adds extra moisture and chew, which keeps the blondies soft in the center. 
  • Vanilla Extract – Adds warm vanilla flavor that plays really nicely with the brown sugar and sourdough.

Nutrition

Calories: 283kcal | Carbohydrates: 40g | Protein: 2g | Fat: 13g | Saturated Fat: 8g | Polyunsaturated Fat: 0.5g | Monounsaturated Fat: 2g | Trans Fat: 0.3g | Cholesterol: 45mg | Sodium: 96mg | Potassium: 78mg | Fiber: 0.5g | Sugar: 26g | Vitamin A: 297IU | Calcium: 35mg | Iron: 1mg
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