Blueberry Muffins Crumb (Print Version)

# Ingredients:

→ Dry Ingredients

01 - Zest from half a lemon
02 - 1 tablespoon corn starch
03 - ½ teaspoon salt
04 - 2 teaspoons baking powder
05 - ½ teaspoon baking soda
06 - 1 cup (150 g) fresh or frozen blueberries
07 - 2 cups (240 g) all-purpose flour
08 - 1 cup (200 g) granulated sugar

→ Wet Ingredients

09 - ½ cup (125 g) sourdough starter discard
10 - 2 large eggs
11 - 8 tablespoons (113 g) butter, melted
12 - 1 teaspoon (5 g) vanilla extract
13 - 3 tablespoons (45 g) sour cream or plain Greek yogurt

→ Crumb Topping

14 - ½ cup (100 g) granulated sugar
15 - 3 tablespoons (45 g) melted butter
16 - ½ cup (60 g) all-purpose flour

# Instructions:

01 - Use a fork to mash the flour, sugar, and butter together in a bowl. Once it forms a crumbly texture, leave it aside for later use.
02 - Heat your oven to 350°F (176°C). Either line your muffin tin with paper liners or grease it generously so nothing sticks.
03 - Stir the flour, sugar, baking powder, corn starch, lemon zest, salt, and baking soda well in a big bowl. Toss in the blueberries so they get lightly coated in the dry mix. This keeps them from sinking while baking!
04 - In a medium-sized bowl, whisk the wet ingredients until smooth. Pour this into the mixture of dry ingredients and stir until combined. If it feels thick, add a little water or milk (about 1-2 tablespoons) until it loosens up.
05 - Spoon the batter evenly into your 12 muffin cups. Generously scatter the crumb topping over each one, and lightly press so it stays in place.
06 - Bake for 30-35 minutes. They're ready when a toothpick poked in the middle comes out clean. Let them cool for about 10 minutes in the tin before transferring to a cooling rack.

# Notes:

01 - Muffins will stay fresh at room temperature for 2-3 days if loosely covered.
02 - Wrap tightly in plastic and freeze them for up to 3 months if you need them to last longer.