Ultimate Recipe for Irresistible Blueberry Muffins

Preheat the oven to 400 degrees F (200 degrees C). Grease 16 muffin cups with cooking spray or line with paper liners.

Make topping: Combine flour, brown sugar, cinnamon, and salt in a small bowl. Cut butter into flour mixture with 2 knives or a pastry blender until crumbly. Set topping aside.

Make muffins: Whisk together 2 cups flour, baking powder, cinnamon, and salt in a large bowl, making a well in the center. Whisk together eggs, granulated sugar, and brown sugar in a separate bowl. Stir in sour cream, oil, and vanilla until well combined. Pour into well and stir until batter is just combined without overmixing. Toss blueberries with 1 tablespoon flour in a small bowl and gently fold into batter.

Spoon batter into the prepared muffin cups, filling each 3/4 full. Sprinkle each muffin with about 1 tablespoon topping.

Bake in the preheated oven until tops spring back when lightly pressed and muffins are lightly browned, 18 to 22 minutes. A toothpick inserted into the center of muffins should come out clean. Cool in the pan for 10 minutes. Transfer to a wire rack to cool completely.