Stir in brown sugar. Cut butter into dry ingredients until mixture resembles coarse meal. Add sweet potato, pecans and 2 T. whipping cream. Stir just until moistened. Turn out dough and bread gently until dough holds together.
Place biscuits on baking sheet.
Combine egg and 1 T. whipping cream. Brush tops with mixture. Bake 12-15 minutes. Serves about 18 biscuits. Top with glaze of 1 cup powdered sugar and 2 T. Milk.