Preheat oven to 350°F (175°C) and line a 12-cup muffin tin with paper liners.

In a medium bowl, whisk together flour, baking powder, and salt until aerated.

In a separate large bowl, cream together the softened butter and sugar using an electric mixer until light and fluffy.

Beat in the egg and vanilla extract until the emulsion is smooth.

Gradually add the dry ingredients to the wet ingredients, alternating with the milk, and mix until just incorporated.

Divide the batter evenly among the cupcake liners, filling each approximately two-thirds full.

Bake for 18 to 20 minutes, or until a toothpick inserted into the center of a cupcake comes out clean.

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