In a large mixing bowl, COMBINE flour, baking powder, salt and baking soda.
Using a pastry blender or fork, CUT in the shortening until pieces are pea-sized.
SPRINKLE one tablespoon of buttermilk over part of flour mixture; gently TOSS with fork; PUSH moistened dough to side; REPEAT, using one tablespoon of buttermilk at a time, until all dough is moistened.
FORM dough into a ball (do not overhandle); lightly ROLL dough into a 15-inch circle.
For extra-rich crust, substitute 1/3 cup whipping cream for 1/3 cup buttermilk.
Per Serving (excluding unknown items): 1887 Calories; 106g Fat (50.8% calories from fat); 31g Protein; 201g Carbohydrate; 7g Dietary Fiber; 6mg Cholesterol; 3598mg Sodium. Exchanges: 12 1/2 Grain(Starch); 1/2 Non-Fat Milk; 20 1/2 Fat; 0 Other Carbohydrates.