Place the beef bones and oxtails in a large stockpot, cover with water. Bring the liquid up to a boil and cook for 10 minutes. Remove from the heat and drain. Rinse the pot and bones. Return the bones to the pot and cover with 6 quarts of water. Bring the liquid up to a boil and skim often to remove the foam. When the foam stops rising to the surface, add 3 quarts of water and return to a boil. Char the onions, shallots, and ginger, directly over a gas burner or under the broiler, about 5 to 6 minutes. Tie the charred vegetables, star anise, garlic cloves, and cinnamon stick in a damped cheesecloth. Add the spice bag and parsnips to the simmering broth. Season the broth with salt and pepper. Simmer the liquid for 1 hour. Add the tripe and tendons to the broth and simmer uncovered for 5 hours. Two hours after adding the tripe, add the flank steak and brisket.