These blueberry muffins with a delightful crumble topping offer a burst of fresh blueberries in every bite, complemented by a sweet and buttery crumbly layer on top that adds an irresistible texture.
Preheat the oven to 375°F. Line a muffin tin with paper liners or grease the wells of the tin with cooking spray or butter.
First, prepare the crumble. Combine flour, sugar, brown sugar, apple pie spice and butter. Use a fork to stir together until small crumbs form. Set aside.
In a large bowl, whisk together the flour, sugar, baking powder, baking soda and salt. Stir in the blueberries and toss to coat.
In a small bowl, combine the egg, milk, vanilla extract and oil until incorporated.
Add the wet ingredients to the dry ingredients and stir to combine with a spatula.
Fill the muffin wells 1/2 full with batter. Sprinkle with streusel topping and, if desired, more blueberries.
Bake for 15 to 20 minutes, until golden brown on top and spring back when lightly touched.
Place tin on a wire rack for 10 minutes, then remove the muffins and place on the wire rack to cool completely before storing.