1. Preheat oven to 350F.
2. Mix together the melted butter, sugar, egg, vanilla and milk.
3. Then add in all the dry ingredients.
4. Mix halfway and add in the blueberries.
5. Fold in the blueberries until smooth.
6. Place the batter into muffin liners.
7. Add the crumble topping on top of the muffins.
8. Bake for 22-25 min.
9. Let it cool down and enjoy!!
