Pour 50 ml (2 fl oz) water over the apricots and leave to soak for 2 hours. Bring the lamb to room temperature.

Saute the onion in the butter, then mix with the apricots, breadcrumbs, parsley, walnuts and cinnamon.. Season to taste. Heat the oven to 200C (400F) gas 6.

Lay the boned shoulder skin side down and season. Push the stuffing into the hole left by the bones. Draw the meat in and secure the ends with skewers.

Mix the lemon and orange juices and pour over the lamb. Roast, uncovered, for 30 minutes, basting occasionally. Reduce the heat to 180°C (350°F) gas 4 and continue cooking for 1 1/2 hours, basting every 15 minutes.

Lift the lamb onto a warmed serving dish and remove the skewers. Leave to 'settle' while you make the sauce: pour off the fat from the pan juices and add the stock. Blend the cornflour with a little water and stir this into the pan. Season to taste and bring to the boil. Boil, stirring, until thickened. Garnish the lamb with watercress and serve with new potatoes and the sauce.