Preheat oven to 350º F. Prepare muffin tins with 16 paper liners. Set aside.

In a medium bowl, mix together flour, baking powder, baking soda, and salt. Set aside.

In a large bowl, whisk together melted butter and sugar (the mixture will look gritty). Whisk in eggs, buttermilk, and vanilla extract, mixing well. In three additions, stir in the dry ingredients until combined.

Scoop batter into prepared muffin cups, filling each about half to two-thirds full. Bake until the cupcakes look just set and the top of a cupcake springs back when pressed gently with a fingertip, about 15 to 20 minutes. Using a long skewer or thin spatula, transfer cupcakes from the muffin tin to a rack. Allow to cool completely before frosting.