Preheat your oven to 450 to 500 degrees F.
Slash the fat side of the lamb all over with a sharp knife. Rub the lamb all over with olive oil and season with Miles Smith Farm lamb spices.
Tightly cover the tray with aluminum foil and place in the oven. Turn the oven down immediately to 325 degrees F and cook for 4 hours - it's done if you can pull the meat apart easily with 2 forks.