To serve, shred the lamb and place on serving plates. Place the roast potatoes, parsnips and cabbage next to the lamb. Serve with the mint sauce, gravy and grated chestnuts (if using).

Rest the lamb for 10 minutes before carving. Meanwhile make the gravy. Degrease the juices in the roasting tin and add stock. Bring to the boil and whisk in a little roux to thicken slightly.