Lemon Blueberry Sourdough Loaf (Printable version)

Tangy sourdough loaf swirled with blueberries and lemon, finished with a golden crumble topping.

# What you need:

→ Dough

01 - 2 3/4 cups bread flour
02 - 1/3 cup active sourdough starter
03 - 1/4 cup granulated sugar
04 - 1 large egg
05 - 1/2 cup whole milk, lukewarm
06 - 1/4 cup unsalted butter, softened
07 - 1 teaspoon fine sea salt
08 - Zest of 1 large lemon

→ Blueberry Swirl

09 - 1 1/2 cups fresh or frozen blueberries
10 - 1/4 cup granulated sugar
11 - 1 tablespoon lemon juice
12 - 1 tablespoon cornstarch

→ Crumble Topping

13 - 1/3 cup all-purpose flour
14 - 2 tablespoons unsalted butter, cold and cubed
15 - 2 tablespoons light brown sugar
16 - Pinch of salt

# Steps to follow:

01 - In a stand mixer bowl, combine bread flour, granulated sugar, fine sea salt, and lemon zest.
02 - Add sourdough starter, egg, and lukewarm milk to the dry mixture. Mix on low speed to form a shaggy dough.
03 - Add softened butter in small pieces while mixer runs on low speed, continuing until dough becomes smooth and elastic, approximately 8 to 10 minutes.
04 - Transfer dough to a lightly greased bowl, cover with plastic wrap, and allow to rise in a warm location until doubled in volume, about 2 hours.
05 - Combine blueberries, granulated sugar, and lemon juice in a small saucepan. Cook over medium heat until berries burst, approximately 5 minutes. Stir in cornstarch and simmer until thickened, 2 to 3 minutes. Cool completely before use.
06 - Mix all-purpose flour, light brown sugar, and salt in a small bowl. Cut in cold butter cubes using a pastry cutter or fork until mixture resembles coarse breadcrumbs. Refrigerate until assembly.
07 - Punch down risen dough and roll out on a floured surface to a 10 by 14 inch rectangle.
08 - Spread cooled blueberry mixture evenly over the dough surface, leaving a 1 inch border on all edges.
09 - Starting from the short side, roll dough tightly into a log. Place seam-side down in a greased 9 by 5 inch loaf pan.
10 - Cover loaf pan and allow dough to rise until puffy and nearly doubled, approximately 1 hour.
11 - Preheat oven to 350 degrees Fahrenheit. Optionally brush loaf with milk or beaten egg wash, then sprinkle crumble topping evenly over surface. Bake 50 to 55 minutes, tenting with aluminum foil after 30 minutes if browning too rapidly.
12 - Allow loaf to cool in pan for 15 minutes, then turn out onto a wire rack to cool completely before slicing.

# Expert tips:

01 -
  • The sourdough tang plays beautifully against bright lemon and sweet berries, creating flavors that feel sophisticated without requiring fussy techniques.
  • It's crushingly good still warm with butter melting into the crumble, but also keeps perfectly for three days wrapped on the counter.
02 -
  • The cooled blueberry filling is absolutely essential—warm filling will soak into your dough and create a soggy bottom, something I learned the embarrassing way in my first attempt.
  • Your sourdough starter matters more than you think; if it's sluggish, the whole loaf rises slowly and the flavor becomes muted instead of beautifully tangy.
03 -
  • If your kitchen is cold, place the rising dough in an oven with just the light on, or set it near (not on) a heating vent—this creates the perfect warm environment without overheating.
  • The secret to a crumble that stays on top is keeping that butter as cold as possible; some bakers even freeze it for 10 minutes before using it.
Return