Preheat oven to 450°. In mixing bowl, combine the flour, sugar, baking powder, baking soda, salt and cayenne pepper.  Cut in the 1/4 cup shortening with a pastry blender, two forks or your finger tips. Gradually add the buttermilk, stirring just until dry ingredients are moistened. Dough should be slightly sticky. Don't overwork the dough.

On lightly floured surface, roll out to 1/2- 3/4" thickness. Cut the biscuits with a 3" biscuit cutter. Put about 1-2 tablespoons of shortening on a cookie sheet with edge and put in hot oven until melted. Place the biscuits in the hot pan. Brush tops with melted butter and bake for 12-14 minutes or until lightly browned.