Chef Michael Gilligan shares his recipe for delicious roast leg of lamb served with mint sauce. 

While lamb has always been associated with spring, there is nothing to stop people from enjoying this delicious dish as fall sets in. 

Today's lamb is a tender creature, except for the shanks, neck, and shoulder, the rest of the beast is tender enough to be cooked by dry heat, like grilling and roasting. Even shoulder and blade chops can be grilled, although, I think they are always better cooked by moist heat, such as braising.

For roasting, nothing beats the leg, especially when coated with lots of garlic, mustard, and rosemary. During grilling months, the leg can be bought butterflied. This boneless uneven hunk can be marinated and cooked on a covered grill, either over direct heat or indirectly.

Genuine spring lamb is born, not killed, in the spring. Born in February or March, these animals are weaned four months later, at which point they graze and fatten exclusively on summer grass. Their meat becomes rich and sweet and takes on a dark hue and a pronounced marbling of creamy-colored fat that matches beautifully with the earthy, forthright flavors of root vegetables and orchard fruit.
The lamb born in autumn is the one who will join the pastel-stained eggs and hollow chocolate bunnies. When you eat it, you will be communing with both seasons, something to keep in mind when you next celebrate spring.


Servings: 6 to 8


1 (6- to 7-pound) bone-in leg of lamb, trimmed of fat and tied
4 large cloves garlic, slivered
Coarse salt
Freshly ground pepper
¼ cup coarse-grain mustard
1 cup very finely chopped fresh mint leaves, washed and dried
2 tablespoons sugar, or to taste
4-6 tablespoons good-quality balsamic vinegar
1-3 tablespoons white wine vinegar


Heat the oven to 450 degrees. Using a sharp paring knife cut thin slits all over the lamb and slide the slivers of garlic in. Season on all sides with salt and pepper. Set on a rack in a roasting pan. Rub the mustard all over the exposed surface.

Roast the lamb for 10 minutes. Reduce the heat to 350 degrees and roast 1 1/4 to 1 1/2 hours, until cooked to the desired doneness. Check after the first hour at lower temperature, using an instant-read thermometer inserted only into the meat, avoiding the bone. A reading of 120 degrees will be rare, 130 medium-rare, 140 for medium; the meat will continue to cook as it sits. Transfer to a carving board and let stand 20 minutes before carving.

While the lamb roasts, place the mint in a deep bowl. Combine the sugar with 1/4 cup of balsamic vinegar and 1 tablespoon of white wine vinegar in a small nonreactive saucepan with ¼ cup water. Heat over medium-low heat until the sugar dissolves, 2 to 3 minutes. Immediately pour over the mint and toss well. Taste and add more sugar or vinegar as needed; the flavor should be sharply minty and sweetly balanced.

To serve, slice the lamb into serving portions and pass the sauce separately to be used judiciously.


What do you call a sheep without legs?
A cloud. 

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* Originally published in 2011. Updated in March 2023.