Preheat oven to 400°.
Lightly spoon flour into dry measuring cups; level with a knife. Combine flour, sugar, salt, and baking powder in a food processor; pulse 4 times. Add shortening; pulse 6 times or until well blended. Add milk and 1/3 cup ice water; process 1 1/2 minutes. (Dough should have a shiny appearance.) Turn dough out onto a lightly floured surface. Cover and let stand 5 minutes.
Uncover dough; roll to about 1/2-inch thickness. Cut dough with a 2-inch round cutter. (Reroll scraps.) Place dough circles on a baking sheet. Pierce tops of dough circles with a fork. Bake at 400° for 18 minutes or until lightly browned.