Shanks: Marinade beef overnight, turning once. Remove beef from marinade, pat dry, and season with salt and pepper. Sear beef in oil on all sides in hot pan, set meat aside.
Brown vegetables in same pan as meat. When vegetables are brown, place meat back in pan and cover with marinade. Bring to a boil. Cover and simmer in 325 degree F oven until meat is falling off bone, about 5 hours. Drain the meat and reserve the strained liquid.
When done, place meat in container covered with strained cooking liquid. Let stand overnight in the refrigerator. Remove meat from cooking liquid. Slice 1/2-inch thick. Place in pan.
Combine 4 cups liquid and demi-glace. Reduce to sauce consistency. Pour sauce over meat and reheat in a 375 degree oven for about 20 minutes.
Serve meat topped with diced glazed carrots and garnish with parsley.
Serving suggestion: 4 carrots, peeled, diced and glazed, chopped parsley.