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" thickness.
Cut with a 2 1/2" biscuit cutter and place on a lightly greased baking sheet.
Bake at 450° for 10-15 minutes or until golden brown.