sift together flour, baking powder and salt, set aside
with stand mixer, beat sugar and butter until light and fluffy
add egg and milk and combine
add in flour, mixing on low. beat until mixture pulls from side of bowl
make 2 disks of dough, place in plastic bag and put in fridge for at least 2 hours (longer is better, so egg protein has a chance to spread)
pre heat oven to 375
powder rolling surface or parchment paper with powdered sugar and roll out dough about 1/4'' thick. you can either pull dough away from cutter and leave shape on parchment paper or transfer the shape to another sheet of parchment paper using a spachula.
place parchment paper on cookie sheet and bake for 9-11 mintues