Preheat oven to 180ºC (356ºC). Line a 12-hole regular cupcake pan with cupcake liners. Set aside.
Melt butter first and then set aside to cool slightly.
In a large mixing bowl, combine flour, baking powder and sugar, mix well.
Pour in milk, eggs, vanilla and the melted butter.
Using a hand mixer, or a stand mixer fitted with the paddle attachment, beat the mixture for 40 seconds on medium speed. Scraping down the sides as needed.
Add blueberries and gently fold through batter until just combined.
Divide batter amongst cupcake liners, filling each up 3/4 of the way full. NOTE: this recipe makes 10-12 cupcakes.
Bake 12-15 minutes or until the tops spring back when lightly pressed or a toothpick inserted into the middle of one cupcake comes out clean.
Cool cakes in pan for 2 minutes.
Transfer cakes to a wire rack to cool completely.