In a medium bowl, beat butter, sugar, egg, milk and vanilla. Next, add 2 cups of flour, baking powder, and salt. Beat until well blended. If the dough is still really sticky you may add in another ¼ to ½ cup of flour.
Divide the cookie dough into 2 equal size portions. Wrap each in plastic wrap and place them in the refrigerator for 1 hour, or until firm.
When ready to bake, preheat the oven to 375 degrees. Remove dough from refrigerator and allow to come to room temperature or until soft enough to roll easily.
On a lightly floured surface, roll dough to ¼ inch thick. Using a 2 ½ inch, lightly floured cookie cutter, cut out as many cookies as possible. Remaining dough pieces can be gathered together and rolled back out to cut additional cookies.Place the cookies 2 inches apart on an ungreased baking sheets.
Bake for 7-10 minutes or until the edges are just golden. These cookies can cook quickly, so start checking at the 5 minute mark. When the cookies are removed from the oven, place baking sheets on cooling racks to allow them to cool completely prior to decorating.