These sourdough blondies are the ultimate dessert bar! The addition of sourdough starter makes these chocolate chunk blondies tender and moist. The classic flavors of brown sugar and vanilla are complimented by the addition of flaky sea salt.
The classic blondie recipe gets an upgrade with this version! It’s still the greatest relative of a brownie, made even better by adding sourdough starter and lots of chocolate chunks.
Ingredients for this recipe:
- Baking Powder
- Kosher Salt
- Flaky Sea Salt
- Dark Brown Sugar
- Vanilla Extract
- Sourdough Starter
- Browned Butter (learn how to make some right here)
- Chocolate Chunks
Blondies are very similar to brownies in how they are prepared. They do not include any cocoa powder or melted chocolate, however, so they have more of a vanilla, cookie-like base. This recipe yields thick, chewy blondies that have shiny and crackly tops that are loaded with pools of gooey chocolate chunks.
How to make chocolate chunk blondies with sourdough starter
- Brown the butter. Do this ahead of time so the butter has time to cool.
- Whisk the dry ingredients. Just flour, baking powder, kosher salt, and flaky sea salt.
- Cream the eggs and dark brown sugar. Then stir in the vanilla extract and sourdough starter.
- Stir in the dry ingredients. And the chocolate chunks, too! Just until there are no dry bits of flour showing.
- Spread into prepared pan. And sprinkle with more chocolate chunks.
- Bake and let cool. I like to sprinkle more flaky sea salt on top of the blondies when they come out of the oven. It makes for the perfect sweet and salty bite!
Does my starter need to be fed and active? I’ve tested this recipe with both an active starter and starter discard straight from the fridge. The great news is it works with both!
Can I use light brown sugar? Yes, light brown sugar works just fine. Dark brown sugar just has a higher molasses content so it will provide a richer, deeper flavor that is unmatched.
How do I brown butter for the blondies? You can find my full how-to tutorial right here.
How long will the bars last? They can be stored at room temperature in an air-tight container for up to a week!
What else can I mix into the dough? You can add in nuts, or white chocolate chips, or even butterscotch chips. Go crazy!
How do I know when the blondies are done? The bars will have risen in the pan, the edges being higher than the center, and they will smell amazing. The color will be deeply golden brown. The top will be shiny and crinkly, like classic brownies and the center will be set.
Other treats to enjoy
- Triple Chocolate Brownies
- Browned Butter Chocolate Chip Cookies
- Sourdough Discard Naan
- Chocolate Mayonnaise Cake
Sourdough Blondies with Chocolate Chunks
- Mixing Bowls
- Hand Mixer
- 9x13 baking pan
- 20 tablespoon unsalted butter
- 3 cups flour
- ¼ tsp. baking powder
- 1 tsp. flaky sea salt such as Maldon, plus more, for serving
- 1 tsp. kosher salt
- 2 ¼ cups dark brown sugar
- 2 eggs straight from the fridge
- 1 tablespoon vanilla extract
- ½ cup sourdough starter
- 2 ½ cups chocolate chunks divided
- Brown the butter about an hour before making the dough. You can find an entire step-by-step guide on how to brown butter here.
- When ready to bake, preheat the oven to 325 degrees. Lightly coat a 9x13 light metal pan with baking spray, place a large piece of parchment paper longwise across the pan so that a few inches of paper hang over the edges, like handles. You can secure the edges of the paper with metal clips, if desired.
- In a medium bowl, whisk together the flour, baking powder, 1 tsp. of the flaky salt, and kosher salt and set aside.
- In a large bowl, combine the dark brown sugar and eggs with a hand mixer on medium until smooth. Add the vanilla and sourdough starter, mixing again to combine. Scrape down the bowl before adding the cooled browned butter. Mix until thick and glossy, about a minute more.
- Add the dry ingredients and 2 cups of the chocolate chunks to the wet ingredients. Stir with a study wooden spoon or rubber spatula, until just combined and no dry streaks of flour remain.
- Spread batter into prepared pan and sprinkle with remaining chocolate chunks. Bake in preheated oven for 40 – 45 minutes, or until edges are risen and begin to pull away from the pan and the top of the blondies are deeply golden, shiny, and krinkly.
- Remove from oven and immediately sprinkle with a generous dose of more flaky sea salt, if desired.
- Cool bars completely on wire rack before slicing and serving.