Sugar Cookies

2/3 C softened butter 
3/4 C sugar 
1 tsp baking powder 
1/4 tsp salt 
1 egg
1 Tbsp milk
1 tsp vanilla
2 C flour

Mix together butter, sugar, baking powder, and salt. Add the egg, milk, and vanilla and beat until fluffy. Mix in flour. Refrigerate dough for at least 30 minutes. Preheat oven to 375 degrees. Roll dough out to 1/8 in thick and cut out. Bake for 7 - 9 minutes on greased baking sheet.