If your sourdough starter has been sitting in the fridge all week, these muffins are exactly what it was waiting for. These Sourdough Blueberry Muffins are everything a great muffin should be — tall, domed, tender inside, with a golden crumb topping that crackles when you bite through it. The sourdough discard adds a subtle tang that plays beautifully against the sweet blueberries and bright lemon zest.
The best part? No yeast, no rise time, no complicated technique. You mix the batter in two bowls, fold in the blueberries, top with the crumble, and bake. Start to finish in under an hour. They come out looking like they came straight from a bakery case — and they taste even better.
Why You’ll Love This Recipe
These muffins hit every note. The batter comes together in minutes with no mixer required — just two bowls and a rubber spatula. The sourdough discard keeps the crumb incredibly moist and adds a depth of flavor you simply don’t get from a standard muffin recipe. The lemon zest brightens everything up without being overpowering, and the crumb topping adds that bakery-style crunch that makes these impossible to stop eating.
They also freeze beautifully, which means you can make a full batch on Sunday and have a grab-and-go breakfast ready for the entire week. Warm one up for 30 seconds in the microwave and it tastes freshly baked.
Ingredients
Here is everything you need. Full measurements are in the recipe card below.
For the Muffins: All-purpose flour, granulated sugar, baking powder, baking soda, salt, cornstarch, lemon zest, fresh or frozen blueberries, melted unsalted butter, eggs, sourdough discard, sour cream, and vanilla extract.
For the Crumb Topping: All-purpose flour, granulated sugar, and cold cubed butter. That’s it — three ingredients that come together in under two minutes.
Equipment: You’ll need a standard 12-cup muffin tin, a large and medium mixing bowl, a whisk, and a rubber spatula. A cookie scoop is optional but makes portioning the batter much easier and more even.
How to Make Sourdough Blueberry Muffins
Step 1: Make the Crumb Topping
Start with the crumb topping so it has time to chill while you make the batter. In a small bowl, combine the flour and sugar, then add the cold cubed butter. Use your fingertips or a fork to work the butter into the flour until you have coarse, sandy crumbs. Pop it in the refrigerator — cold crumb topping holds its texture better during baking and gives you that satisfying crunch.
Step 2: Mix the Dry Ingredients
In a large mixing bowl, whisk together the flour, sugar, baking powder, baking soda, salt, cornstarch, and lemon zest. The cornstarch is the secret weapon here — it keeps the muffins tender and prevents a dense, gummy crumb. Make sure everything is evenly distributed before adding the wet ingredients.
Step 3: Mix the Wet Ingredients
In a separate medium bowl, whisk together the melted and cooled butter, eggs, sourdough discard, sour cream, and vanilla extract until smooth and well combined. Make sure the butter is fully cooled before adding the eggs — you don’t want scrambled eggs in your muffin batter.
Step 4: Coat the Blueberries
Before folding the blueberries into the batter, toss them in a tablespoon of the dry flour mixture. This simple trick prevents them from sinking to the bottom of the muffins during baking. If you’re using frozen blueberries, add them straight from frozen — do not thaw first, or they’ll bleed purple into the batter.
Step 5: Combine and Fold
Pour the wet ingredients into the dry ingredients and fold gently with a rubber spatula until just combined. This is the most important step: do not overmix. Overmixing develops gluten and turns your muffins tough and dense. A few streaks of flour are completely fine. Fold in the flour-coated blueberries with a few gentle strokes.
Step 6: Fill the Tin and Add Crumb Topping
Divide the batter evenly among the 12 lined muffin cups, filling each about two-thirds full. A cookie scoop makes this quick and ensures even portions. Retrieve the crumb topping from the refrigerator and generously sprinkle it over each muffin, pressing gently so it adheres to the batter.
Step 7: Bake
Bake at 375°F for 30–35 minutes, or until the tops are deep golden brown and a toothpick inserted into the center of a muffin comes out clean. Every oven is different — start checking at 28 minutes. Let the muffins cool in the tin for 5–10 minutes before transferring to a wire rack.
Tips for the Best Muffins
- Don’t overmix. Fold until just combined — a few streaks of flour are fine. This is the single most important rule for tender muffins.
- Coat the blueberries in flour. It takes 30 extra seconds and makes a real difference in where the berries end up.
- Use cold butter in the crumb topping. Warm butter will melt into the batter instead of forming crumbs.
- For extra-tall bakery domes, bake at 400°F for the first 5 minutes, then reduce to 375°F for the remainder. The initial blast of heat causes rapid rise.
- Frozen blueberries work great — just don’t thaw them. Add straight from the freezer to prevent streaking.
- Make-ahead friendly. The crumb topping can be made up to 2 days ahead and stored in the refrigerator.
Variations
These muffins are endlessly adaptable. Swap the blueberries for raspberries, blackberries, or diced strawberries. Add a teaspoon of cinnamon to the dry ingredients for a warmer flavor profile. For a lemon glaze, whisk together ½ cup powdered sugar with 1–2 tablespoons fresh lemon juice and drizzle over the cooled muffins. You can also fold in a handful of white chocolate chips alongside the blueberries for a bakery-style twist.
Storage
Store leftover muffins in an airtight container at room temperature for up to 3 days. For longer storage, freeze in a zip-top freezer bag for up to 3 months. Thaw at room temperature or warm in the microwave for 30 seconds. They taste freshly baked.
If you make these Sourdough Blueberry Muffins, leave a comment below and let me know how they turned out. And if you’re looking for more ways to use your sourdough discard, check out the Sourdough Discard Coffee Cake and Sourdough Discard Brownies — both are just as easy and just as good.
Sourdough Blueberry Muffins with Crumb Topping
Equipment
- Standard 12-cup muffin tin
- Paper or foil cupcake liners
- Large mixing bowl
- Medium mixing bowl
- Rubber Spatula
Ingredients
For the Muffins
- 2 cups all-purpose flour
- 1 cup granulated sugar
- 2 tsp baking powder
- ½ tsp baking soda
- ½ tsp salt
- 1 tbsp cornstarch
- 1 lemon, zested
- 1 cup fresh or frozen blueberries
- 8 tbsp unsalted butter, melted and cooled (1 stick)
- 2 large eggs
- ½ cup unfed sourdough discard
- 3 tbsp sour cream
- 1 tsp vanilla extract
For the Crumb Topping
- ¼ cup all-purpose flour
- 2 tbsp granulated sugar
- 1 tbsp unsalted butter, cold and cubed
Instructions
Make the Crumb Topping
- In a small bowl, combine ¼ cup all-purpose flour and 2 tablespoons granulated sugar. Add 1 tablespoon cold, cubed butter. Using your fingertips or a fork, cut the butter into the flour and sugar until coarse crumbs form. Refrigerate while you prepare the batter.
Make the Muffin Batter
- Preheat your oven to 375°F. Line a standard 12-cup muffin tin with paper or foil cupcake liners. Set aside.
- In a large mixing bowl, whisk together the flour, sugar, baking powder, baking soda, salt, cornstarch, and lemon zest until well combined with no lumps.
- In a separate medium bowl, whisk together the melted butter, eggs, sourdough discard, sour cream, and vanilla extract until smooth and well combined.
- Toss the blueberries with 1 tablespoon of the measured flour to coat them — this prevents them from sinking to the bottom of the muffins.
- Pour the wet ingredients into the dry ingredients. Using a rubber spatula, gently fold until just combined — a few streaks of flour are fine. Do not overmix. Gently fold in the flour-coated blueberries.
- Divide the batter evenly among the 12 prepared muffin cups, filling each about two-thirds full. An ice cream scoop makes this easy.
- Retrieve the crumb topping from the refrigerator. Generously sprinkle it over the top of each muffin and gently press so it adheres.
- Bake for 30–35 minutes, until the tops are golden brown and a toothpick inserted into the center comes out clean. Cool in the tin for 5–10 minutes, then transfer to a wire rack.
Notes
– Do not thaw frozen blueberries before folding them in — they’ll bleed less into the batter.
– Do not overmix the batter; a few streaks of flour are perfectly fine and will result in a more tender crumb.
– The cornstarch is not optional — it keeps the muffins soft and bakery-style tender.
– Tossing blueberries in flour before folding them in prevents them from sinking.
– These muffins are best eaten the day they are baked, but they reheat beautifully in a 300°F oven for 5 minutes.
