2 cups self-rising flour, 1/4 cup packed brown sugar, 1 t. cinnamon, 1 t. ginger, 7 T. cold butter, divided, 3 T. shortening, 1 cup mashed sweet potatoes, 6 T. milk.
In a bowl, combine flour, brown sugar, cinnamon and ginger. Cut in 4 T. butter and shortening until mixture resembles coarse crumbs. In another bowl, combine sweet potatoes and milk; stir into crumb mixture just until combined.
Turn onto a floured surface; knead 8 - 10 times. Roll to 1/2" thickness; cut with a 2 1/2" biscuit cutter. Place on ungreased baking sheets. Melt remaining butter; brush over dough. Bake at 425 degrees for 10 -12 minutes or until golden brown. Remove to wire racks. Serve warm. Makes 1 1/2 dozen.