These cookies are crisp and buttery, and they keep well, if you can keep them hidden!
Preheat oven to 375 degrees F.
In a bowl, cream butter and sugar. Add egg, orange juice, and vanilla and mix well. Add flour and baking powder. Cover dough and chill for 2 to 3 hours, or until firm.
Roll out portions of dough to ¼ inch thick, keeping the rest chilled. Cut out with cookie cutters. Sprinkle some of the cookies with colored sugar before baking, if desired. Place onto ungreased cookie sheets and bake for about 8 minutes, or until lightly browned.