Season the meat with a mixture of 2 tablespoons each of sea salt, paprika powder, garlic granulate, chili powder and 1 tablespoon each of mustard powder and black pepper, ideally 1 day in advance.
Put the meat including the bones with the stewing ingredients red wine vinegar, water, 3 tablespoon soy sauce in a bowl, the meat should be about half covered, cover with aluminum foil and stew in the oven at about 100 degrees for about 6 hours. Turn the meat every 2 hours so that both sides can bathe.
For the marinade, heat apple juice, ketchup, 1 tablespoon soy sauce, 1 tablespoon molasses and 1/2 teaspoon each of chili powder, garlic granulate, mustard powder, sea salt and black pepper in a pan and simmer for about 5 minutes.
After 6 hours, take the meat out of the oven, pour off the stewed sauce and pour the warm marinade over the meat. Let rest for about 15-20 minutes so that the meat absorbs the marinade nicely.