Christmas Sugar Cookies

The BEST Sugar Cookies:
1 1/2 cups butter, softened
2 cups sugar
4 eggs
1 tsp. vanilla
5 cups flour
2 tsp. baking powder
1 tsp. salt
Cream together butter and sugar until smooth. Beat in the eggs and vanilla. Mix in the flour, baking powder and salt. Cover and chill at least one hour.
Preheat oven to 400 degrees F. (200 degrees C.)
Roll out dough on floured surface 1/4-1/2 inch thick. Cut into shapes.
Bake 7-9 minutes. Cool slightly on baking sheets and then transfer to cooling rack and cool completely.
Frost with your favorite butter-cream frosting.