In a bowl, combine flour, sugar, baking powder, salt and cream of tartar.
Cut in shortening until mixture resembles fine crumbs.
In a small bowl, beat egg and milk; stir into dry ingredients just until moistened.
Turn onto a lightly floured surface; roll to 1/2-in.thickness.
Cut with a 2-1/2-in.biscuit cutter.
Bake at 400° for 12-15 minutes or until golden brown.