Sift dry ingredients; cut in shortening until mixture resembles coarse meal. Sprinkle buttermilk evenly over flour mixture, stirring until ingredients are moistened. Turn dough out onto a lightly floured surface; knead lightly 4 to 5 times.
Pat dough out to 1/2-inch thickness; cut with a 2 1/2-inch biscuit cutter. Place biscuits on a lightly greased baking sheet. Bake at 450° for 10 to 12 minutes or until lightly browned.