Seasoned the leg of lamb with salt and pepper. Using sharp knife to pierce the meat and stuff in cut garlic, shallots and rosemary. (If u do not have rosemary, u could substitute it with ginger, rub with oyster sauce and 5 spice powder for Chinese version) Roast in the preheated oven at 180ºc for about 1.5 to 1.45 hour for pink meat depending on size. 2 hrs to 2.20hrs for well done. Above cooking time is based on meat put directly on roasting pan as if put on rack, it take slightly longer.