THE DAY BEFORE GRILLING THE RIBS, put the sugar and vinegar in a pot large enough to hold the ribs and place over medium heat on top of the stove. Cook until the vinegar reduces and forms a syrup with the sugar, about 8 minutes. Watch carefully, as the syrup will suddenly darken in color. Immediately add the broth, water, catsup, tomato paste, mustard, Worcestershire, cloves, chili powder and pepper and bring to a boil. Add the ribs and cook 20 minutes. (If using chicken, cook for 10 minutes.)
Remove from heat, remove the ribs from the liquid and place covered in the refrigerator. Cook the liquid over medium heat until it becomes thick and syrupy. The next day, light a charcoal grill. Place the ribs on the grill so they are not directly over the coals and cover the grill so that smoke collects inside. If your grill does not have a cover, improvise one out of aluminum foil.
Cook for 40 minutes, basting with barbecue sauce every 10 minutes. When ribs are well heated, remove to a platter and serve. Offer any additional barbecue sauce on the side.