A juicy leg of lamb carved into small pieces can be the centerpiece of an hors d'oeuvres buffet.
Remove papery skin, or fell, from lamb and trim fat on top side to 5/8 inch thick. (You can also have your butcher do this.) Remove all fat from bottom side of leg. With the tip of a sharp knife, cut a few slits in flesh on top and bottom of lamb and insert garlic slivers.
Combine oil, lemon juice, oregano, chopped rosemary, and salt and pepper to taste in a small mixing bowl. Rub lamb well with half the marinade, and refrigerate, covered, for several hours or overnight. Set aside remaining marinade.
Remove lamb from refrigerator one hour before you are ready to cook it. Heat oven to 450 degrees. Arrange rosemary sprigs along both sides of leg and secure rosemary in 3 places with butcher's twine. Season well with salt and pepper and place in a roasting pan.
Place lamb in oven and turn down heat to 325 degrees. Baste often with remaining marinade. Drain fat from pan periodically. Roast lamb until a meat thermometer reads 135 degrees when inserted into thickest part for medium rare, about 1 hour and 20 minutes, or continue cooking to desired temperature. Untie lamb and let rest for 15 minutes before slicing. Carve and serve with condiments and pita.