PREPARATION:

1. For cookies, beat 1-1/2 cups butter and granulated sugar in large bowl until creamy. Add egg yolks; beat until light and fluffy. Add flour, baking powder, orange juice and 1 teaspoon vanilla; beat until well mixed. Wrap dough in plastic wrap; refrigerate 2 to 3 hours or until firm.
2. Preheat oven to 350°F. Roll out dough, half at a time, to 1/4-inch thickness on well-floured surface. Cut dough with holiday cookie cutters. Place 1 inch apart on ungreased cookie sheets. Bake 6 to 10 minutes or until edges are golden brown. Remove to wire racks; cool completely.
3. For frosting, beat powdered sugar, butter, milk and vanilla in bowl until fluffy. If desired, divide frosting into small bowls and tint with food coloring. Frost cookies; decorate as desired.