Blueberry Streusel Muffins

Ingredients

For the Crumb Topping (Streusel):

• 1/2 cup all-purpose flour
• 1/4 cup brown sugar (packed)
• 2 tbsp granulated sugar
• 1/2 tsp ground cinnamon
• 3 tbsp unsalted butter, melted

For the Muffin Batter:

• 2 cups all-purpose flour
• 1 tbsp baking powder
• 1/2 tsp baking soda
• 1/2 tsp salt
• 1/2 tsp ground cinnamon
• 1/2 cup unsalted butter, softened to room temperature
• 3/4 cup granulated sugar
• 2 large eggs (room temperature)
• 1/2 cup sour cream (or full-fat Greek yogurt)
• 1/2 cup milk
• 2 tsp vanilla extract
• 1 1/2 cups fresh blueberries (or chocolate chips)

Instructions

1. Make the Crumb Topping

1. In a small bowl, mix the flour, brown sugar, granulated sugar, and cinnamon.
2. Pour in the melted butter and stir with a fork until the mixture forms thick clumps and crumbs. Set aside in the refrigerator while making the batter.

2. Prepare the Batter

1. Preheat your oven to 215°C (425°F). Line a 12-cup muffin tin with paper liners or grease it well.
2. Dry Ingredients: In a medium bowl, whisk together the flour, baking powder, baking soda, salt, and cinnamon.
3. Wet Ingredients: In a large bowl using a hand mixer (or stand mixer), beat the softened butter and granulated sugar together on high speed until smooth and creamy (about 2 minutes).
4. Add the eggs one at a time, beating well after each. Stir in the sour cream, milk, and vanilla extract until combined.
5. Combine: Pour the dry ingredients into the wet ingredients. Fold gently with a spatula just until combined. Do not overmix; the batter will be very thick. Gently fold in the blueberries.

3. Assemble and Bake

1. Spoon the batter evenly into the 12 muffin cups, filling them all the way to the top.
2. Press the prepared crumb topping generously onto the top of each muffin, pushing it slightly into the batter so it sticks.
3. The Baking Trick: Bake at 215°C (425°F) for exactly 5 minutes. Then, keeping the muffins in the oven, turn the oven temperature down to 180°C (350°F) and bake for an additional 15–18 minutes until the tops are golden brown and a toothpick comes out clean.