Preheat the oven to 325 degrees F. Heat the oil in large skillet. Season the lamb with salt and pepper and then brown well on all sides. Set the shanks in a single layer in a casserole. Remove all but 1 Tbsp. of the fat from the skillet. Add the onions and garlic and cook 3-4 minutes. Add remaining ingredients, except parsley, and bring to a simmer. Pour mixture over lamb. Cover and bake the lamb until it falls off the bone tender, about 2 to 2-1/2 hours. Skim any fat from the surface, sprinkle with parsley and serve.