Step 1 In a very large pot, combine the onions, celery, carrots, rosemary, cloves, peppercorns, short ribs, brisket, oxtail, calf's foot and tongue, chicken and garlic. Add enough water to cover all of the meats and vegetables, and bring to a boil. After 10 to 15 minutes, reduce the heat and continue to simmer to gently cook the meats.
Step 2 While the meats are stewing in the large pot, in a smaller pot cover the sausage with enough water to cover. Bring to a simmer and cook until the sausage is firm and cooked through, about 1 hour. Drain and hold in a warm place.
Step 3Continue to cook the meats in the large pot until each are cooked through, 1 to 21/2 hours, then remove to a platter and hold in a warm place. The chicken will be done when the meat is firm, the joints move easily and a thermometer inserted into the meat between the breast and thigh reaches 165 degrees, about an hour. The short ribs, brisket and oxtail will be done when a knife pierces easily, about 2 hours. The tongue will also be done when a knife pierces easily, 1 to 2 hours, depending on the size of the tongue; as soon as the tongue is done, remove and peel the outer layer of skin while the tongue is hot (the skin will be harder to peel as the tongue cools).
Step 4Strain the vegetables and flavorings from the broth, and bring the broth to a simmer to reduce it slightly, 20 to 30 minutes. While the broth is reducing, prepare the sauces.
Step 5When the broth is almost ready, carve the meats and arrange on the platter. Spoon a little broth over the meats to moisten, and serve with the bagnèt verd and, if you like, the hazelnut and honey sauce and a jar of mostarda.