Wash the liver under running water and then blanch by pouring over salted boiling water. Drain and dip into the seasoned flour coating carefully on each side. Fry quickly in hot fat. Remove from the pan and then quickly the potatoes and onions in the same dripping. Lay layers of liver, onions and potatoes in a 3-pint casserole dish. Chop the bacon rashers roughly and sprinkle over the top. Pour on stock, cover and cook at gas mark 5, 375 F (190 C) for 30 minutes.