Heat duck fat in fry pan, before adding the oxtail and browning on all sides. Transfer the meat to the casserole dish. Deglaze the frying pan with vinegar, then add sugar and reduce to caramel. Add the stout and reduce by ½. Next add the port and boil for 2 minutes Add the stock and pass onto the oxtail, before adding a little water if necessary. Place the herbs and spice into the middle of the casserole, cover and cook for 2 hours on 115°c, gently simmering. Add the onions and carrots and simmer for a further 1½ hours or until the meat comes away from the bone easily. Finish with the figs or prunes, adding them to the pot for the final 30 minutes. Serve with all butter mashed potato or fresh ribbon noodles.