Mix sifted flour, salt, baking powder, then shortening until it resembles coarse meal. Add milk to mixture only until flour is dampened. Knead gently on floured board, roll into 5 x 12-inch rectangles 1/4 inch thick. Spread cheese to within 1/4 inch of edge. Over that, spoon relish. Roll into cylinder and seal edges with water. Cut into 1/2-inch slices. Roll edges around in a little flour and pat edges firmly. Bake 12 to 15 minutes at 425°.