Preheat oven to 350.
With your mixer using a paddle attachment, mix butter and sugar until light and fluffy on medium high. Beat in each egg one at a time until fully blended. Mix in vanilla.
In a medium bowl, combine flour, baking powder, baking soda, and salt.
On low speed and starting with the dry ingredients, blend in batches switching between dry and milk. End with mixing in the dry ingredients.
Fill cupcake liners 2/3 full and bake for 16-18 minutes.