Preheat the oven to 375 degrees. Place cupcake liners in each of 24 muffin cups. Set aside.

In a medium bowl combine the flour, baking powder, and salt.

In a large bowl cream the butter, sugar, and brown sugar. Mix well. Add in the eggs one at a time, stirring after each addition. Stir in the vanilla.

Add half of the flour mixture to the butter mixture and mix well. Add in the milk and stir until combined. Add the remaining flour and mix until just blended.

Pour the batter into the prepared muffin cups, filling 3/4 of the way full.

Bake for 20-25 minutes or until a toothpick inserted into the center comes out clean. Cool on a wire rack.

To make the frosting beat the butter with a mixer. Add the powdered sugar 1/2 cup at a time until desired consistency is reached. Stir in the vanilla and a few tablespoons of milk.

Divide into 4 bowls and color with neon food coloring. Place two colors in each of two piping bags, being careful to keep one color on one side of the bag and the other on the other side of the bag. This will help the color swirl on the cupcake.

Pipe the frosting on the cupcakes and top with a sugar skull.