Place half of the sliced onions on the bottom of the crock pot. Place meat on top along with cloves and the remaining sliced onions. Add water, cover and cook 8-12 hours or overnight on LOW.
Remove meat from crock pot. Drain liquid from crock pot and discard. Remove bone and fat from meat; shred meat; return to crock pot. Add chopped onion and barbecue sauce. Cover and cook another 1-3 hours on HIGH or 4-8 hours on LOW, stirring 3 or 4 times. Serve from crock pot on large toasted buns.
Servings: 4 to 6