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Roast Leg of Lamb with Pungent Mustard by Anne Dolamore

July 27th, 2020

This is an excellent roast for either a small family dinner or for a larger party. If you would like to serve 8 to 10 people, roast a whole leg of lamb weighing 2.7-3kg. Figure the cooking time at about 16 minutes per 1/2kg for medium-rare (internal temperature of 57-60°C/135-140°F). Serve with Rosemary Roast Potatoes and a green vegetable.

Serves 4–6

1 rump half leg of lamb (about 2kg/4

pounds, bone in for more flavour)

2 cloves garlic, peeled and halved

2 teaspoons fresh thyme or 1 teaspoon dried thyme

1 teaspoon fresh or dried rosemary

110g/8 tablespoons (1 stick) unsalted butter, melted

1 small onion, peeled and quartered

1 carrot, peeled and quartered

2 cloves garlic, unpeeled and crushed with the flat of a knife

1 bay leaf

Salt and freshly ground black pepper to taste

3 tablespoons dried breadcrumbs

1 tablespoon finely chopped fresh parsley

2 tablespoons Tierenteyn or Dijon mustard

120ml/½ cup dry white wine or veal stock

120ml/½ cup water

1 bunch watercress, large stems removed, for garnish


Place the leg of lamb in a deep flameproof roasting tin. Rub the meat on all sides with the cut sides of the halved garlic cloves. (Garlic lovers can stud the meat with fine slivers of garlic.) Sprinkle with the thyme and rosemary; pour the melted butter over the meat. Cover the roasting tin with clingfilm and refrigerate for at least 1 hour or up to 8 hours.

Preheat the oven to 200°C/400°F/gas 6. Surround the roast with the onion, carrot, the crushed garlic cloves, and bay leaf. Season with salt and pepper.

Roast the lamb for 15 minutes. Reduce the heat to 180°C/350°F/gas 4 and continue roasting for 45 to 50 minutes. Baste the meat every 15 minutes or so with the pan drippings, adding a little water if the tin is too dry. The roast is done when the internal temperature registers 57°C/135°F on an instant-read thermometer. At this point, the meat will be rare, but it will continue to cook a while longer as it sits.

Combine the breadcrumbs and parsley. Spread the lamb evenly with the mustard and pat on the breadcrumbs and parsley mixture. Baste with the drippings and return to the oven. Roast for another 10 minutes to crisp up the breadcrumbs.

Transfer the roast to a cutting board and let it rest for 15 minutes before carving. Remove as much fat as possible from the roasting tin. Place the tin on top of the stove and add the white wine and water. Deglaze over high heat, scraping up all the brown bits from the bottom with a wooden spoon.

Strain the gravy, pressing as much juice as possible from the vegetables with the back of a wooden spoon. Taste and adjust the seasoning and pour it into a gravy boat. Carve the leg of lamb and arrange the slices on a platter surrounded by small sprigs of watercress.