In a bowl, combine the flour and baking powder. Mix them well.
In another bowl, whisk together the melted butter, sugar, milk, egg, and vanilla extract until smooth.
Gradually add the wet mixture to the dry mixture, stirring until just combined.
Gently fold in the blueberries. Be careful not to overmix; you want those plump blueberries to stay whole.
Preheat your oven to 375°F (190°C) and line a baking sheet with parchment paper.
Using an ice cream scoop or a spoon, drop portions of the muffin top batter onto the prepared baking sheet.
Bake in the preheated oven for 12-15 minutes or until the muffin tops are golden brown and a toothpick inserted comes out clean.