Combine flour, baking powder, and salt; set aside.
Beat butter, shortening, and sugar at medium speed with an electric mixer until blended. Add eggs, 1 at a time, beating until blended after each addition. Stir in lemon rind, if desired, and vanilla extract.
Add flour mixture to sugar mixture, beating until blended. Cover and chill 8 hours.
Roll dough to 1/4-inch thickness on a lightly floured surface; cut with a 3-inch angel cookie cutter. Place on lightly greased baking sheets.
Bake at 350° for 8 minutes or just until edges begin to brown. Remove to wire racks to cool. Decorate as desired with Buttercream Frosting.
*1 can of ready-to-spread cream cheese frosting may be substituted.