Preheat the oven to 375°F (190°C) and grease the muffin tin.

In a large bowl, whisk together flour, sugar, baking powder, and salt.

In another bowl, mix milk, melted butter, eggs, and vanilla extract until combined.

Pour the wet ingredients into the dry ingredients and stir until just combined. Gently fold in the blueberries.

In a small bowl, combine flour, brown sugar, and cinnamon.

Add the cold butter and mix with a fork or your fingers until crumbly.

Spoon the muffin batter into the prepared muffin tin, filling each cup about 2/3 full.

Sprinkle the crumble topping evenly over each muffin.

Bake for 18-20 minutes or until a toothpick inserted in the center comes out clean.

Let cool in the pan for 5 minutes before transferring to a wire rack to cool completely.