Beat butter and sugars together until light and fluffy. Add the eggs, milk, and vanilla and re-mix.
Combine the flour, baking powder, and salt, and blend it into the batter.
Cover and chill in the fridge 3-4 hours.
Roll out the dough on a lightly floured counter, board, or rolling pin cloth. Be sure to also flour the rolling pin or dough will stick. Cut into shapes about 1/4 inch think and place on a cookie sheet on top of parchment paper.
Bake at 375 degrees for 8-10 minutes or until the edges are very light, light brown. Cool completely and decorate as desired.