Basic Cookie Dough

2-1/2 c butter, softened
2 c sugar
2 large eggs, room temperature
1/4 c milk
2 t vanilla
8 c flour
4 t baking powder
1 t salt

Cream butter and sugar. Add eggs, milk and vanilla. Sift together dry ingredients, add gradually to egg mixture. Divide dough into four two-cup portions, cover and refrigerate until ready to use.