Start by setting the oven to 350°F (175°C) and getting a muffin tin ready by adding cupcake liners.
In a medium-sized bowl, combine the baking powder, flour, and salt by whisking them together.
Combine the butter and sugar in a separate bowl, whisking them together until the mixture has a light and fluffy texture.
Beat in the eggs one at a time, and then stir in the vanilla extract.
Gradually add the dry ingredients to the wet mixture in three stages, alternating with the milk, and finishing with the dry ingredients.
Stir until the ingredients are just combined.
Scoop the batter into the cupcake liners, filling them up to 2/3 of their height to allow for expansion.
Place the cupcakes in the oven and bake for 18-20 minutes, or until they're fully cooked and the toothpick inserted in the center comes out clean.
Once out of the oven, wait for 5 minutes before transferring the cupcakes from the muffin tin to a wire rack, allowing them to cool down completely.