1. Place the pork in a big plastic food box and cover it with the water.
2. Add salt, garlic cloves, thyme, and the Grappa, then let the meat marinate for 3 hours.
3. Finely chop the onion and mix it with the parsley.
4. Make a few incisions on the pork meat and stuff them with the onion mixture and the cloves.
5. Put the pork and its marinade into a large roasting dish and bake at 320° F for 30 minutes or until the meat is cooked in and out.