Preheat the oven to 375 degrees F.
Sift together the flour, salt, baking powder, and baking soda. Cut in the shortening using a pastry blender or your hands or a stand mixer fixed with a dough hook until the mixture resembles coarse crumbs. Make a well in the center and add 1 cup buttermilk. Using your hands, quickly fold the dry ingredients into the buttermilk until a sticky dough forms. You may need to add more buttermilk.
Turn the dough out onto a floured surface. Gently fold the dough over itself 3 or 4 times to create layers. Press the dough out to 1 1/2-inches thick and cut with a floured 3-inch biscuit cutter. Lay the biscuits on an ungreased cookie sheet and brush the tops with buttermilk. Bake for 20 to 25 minutes until risen and golden brown.
Recipe courtesy of Tyler Florence, 2007