Preheat oven to 350°F (175°C). Line a muffin tin with cupcake liners.

In a large bowl, cream together the butter and sugar until light and fluffy. Beat in the eggs one at a time, then stir in the vanilla.

In a separate bowl, whisk together the flour, baking powder, and salt. Gradually add the dry ingredients to the wet ingredients, alternating with the milk, beginning and ending with the dry ingredients. Mix until just combined.

Fill cupcake liners 2/3 full. Bake for 18-20 minutes, or until a toothpick inserted into the center comes out clean.

Let cupcakes cool in the tin for a few minutes before transferring them to a wire rack to cool completely.

In a large bowl, beat the butter until light and fluffy. Gradually add the powdered sugar, beating until smooth. Beat in the milk and vanilla extract.

Frost the cooled cupcakes with vanilla frosting and decorate with holiday sprinkles.