INSTRUCTIONS
1
Score meaty side of lamb in a diamond pattern of ¼-inch-deep cuts about 1½ inches apart. Generously season all over with salt and pepper, and place scored-side up in a large roasting pan.
2
In a small bowl, whisk olive oil with lemon juice, lemon zest, garlic, harissa, coriander and cumin. Pour marinade over lamb and massage into crevices. Cover pan with aluminum foil and let sit at room temp to marinate for at least 1 hour.
3
Preheat oven to 450°F. Place roasting pan on middle oven rack; turn heat down to 350°F. Roast, basting lamb with pan juices every ½ hour, until a meat thermometer inserted into thickest part of meat reads 130°F ( medium rare), about 1 to 1½ hours.
4
Remove from oven, tent loosely with foil, and let rest at least 15 minutes before carving. Serve with additional harissa if desired.