Dissolve yeast in warm water. Let stand 5 min.
Stir in the buttermilk; set aside.
In a large mixing bowl, combine flour, sugar,
baking powder, soda and salt.
Cut in shortening with a pastry blender
until mixture resembles coarse meal.
Stir in yeast/buttermilk mixture; mix well.
Turn out onto a lightly floured surface;
knead lightly 3-4 times. Roll to a 1/2" thickness.
Cut with a 2 1/2" biscuit cutter.
Place on a lightly greased baking sheet.
Cover and let rise in a warm place about 1 1/2 hours.
Bake at 450F for 8-10 min.
Lightly brush tops with melted butter.
Yield: about 2 1/2 dozen.