In a medium bowl whisk together the flour, baking powder and salt.
In a medium bowl beat butter and sugar for 1 minute then add the egg and vanilla beat just until combined. Add the flour mixture in 2 additions alternating with the milk (1 teaspoon at a time)mix just until combined.
Move the dough to a lightly floured flat surface and gently knead a couple of time into a dough ball, wrap the dough in plastic wrap and refrigerate 60 minutes.
Roll the dough into a ¼ inch thickness then cut out with cookie cutters, place the cut out cookies on parchment paper lined cookie sheets, sprinkle with sprinkles. Chill while the oven is pre-heating.
Pre-heat oven to 350F (180C)
Bake approximately 8-12 minutes or until slightly golden on the edges. Let cool on cookie sheet then move to a wire rack, cool completely before icing if desired. Enjoy!
FROSTING
In a small bowl mix together the powdered sugar and vanilla then gradually add the milk (a little at a time, 1 tablespoon might be too much, because you want it really thick), place in pastry bag and draw an outline on the cookie, top with sprinkles. (I placed the cookie on a plastic plate before sprinkling so I didn't have sprinkles everywhere).
Notes
For room temperature remove from the fridge 45-60 minutes before using. To keep the cookies from spreading it is best to beat the butter and sugar just until combined and not creamed (of course this also depends on the type of cookie), for some cookies including some icing sugar in the mixture also keeps the cookies from spreading. And probably most important of all, is to use a higher protein flour with at least 11.5- 12% protein count. And don’t forget to chill the dough for at least 1 hour and again the cut out cookies before baking. Using most of these will help produce the perfect Christmas Sugar Cookies.The baked cooled cookies should be stored in an airtight container in a cool dry area, they will keep at room temperature for up to 3 days. They can also be refrigerated in an airtight container, they will keep for up to 7-10 days.If you don’t eat them before this then it is best to freeze them. They will keep for up to 3 months in the freezer.