Cookies:

1. In the bowl of a stand mixer fitted with the whisk attachment beat together the butter and sugar.
2. Add the egg and vanilla and beat until fluffy.
3. Add the dry ingredients and mix until combined.
4. Chill for 1-24 hours.

Baking:

1. Preheat oven to 350 F (175 C) and line cookie sheets with parchment paper.
2. If the dough has been in the fridge a long time you may need to let it rest on the counter for 5-10 minutes before rolling it out. Roll out the cookie dough on a lightly floured surface. I like to use wax paper on top to keep the dough from sticking. Roll out to 1/4″ (1/2 cm) thick or a little thinner as evenly as you can.
3. Cut out cookies in your desired shapes and put them on the cookie sheets about 2 inches apart.
4. Bake until the edges of the cookies just start to lightly brown (about 10 minutes).
5. Cool on wire racks.

Icing:

1. Beat together sugar, butter and vanilla. Add milk one tablespoon at a time until it reaches the desired consistency. Keep it thick for spreading with a knife or thin it down to pipe it onto the cookies.
2. Separate into bowls and add colors if desired.
3. Ice the cookies and decorate with sprinkles!