How to Make It
Beat butter at medium speed with an electric mixer until creamy. Gradually add sugar, beating well. Add egg and vanilla, beating well.
Combine flour, baking powder, and salt in a separate bowl; add to butter mixture, beating just until blended. Divide dough into 4 portions. Wrap each portion in plastic wrap, and chill at least 1 hour.
Roll each portion to 1/8-inch thickness between 2 sheets of wax paper. Cut with a 5-inch star-shaped cookie cutter. Place 1 inch apart on greased cookie sheets. Bake at 375° for 7 minutes or until edges lightly brown. Cool 3 minutes on cookie sheets; carefully remove to wire racks, and cool completely. Spread or decoratively pipe cookies with Royal Frosting.