In a bowl, combine the flour, baking powder, baking soda, and salt; cut in shortening until the mixture resembles coarse crumbs
Stir in buttermilk; knead dough gently
Roll out to 1/2 inch thickness
Cut with a 2-1/2 inch biscuit cutter and place on a lightly greased baking sheet
Bake at 450 degrees for 10-15 minutes or until golden brown