Place onions in a 5-qt. slow cooker. In a small bowl, combine the garlic, salt and pepper. Cut roast in half; rub with garlic mixture. Put roast in the slow cooker and add bay leaves.
In a small bowl, combine hot water and honey; stir in the soy sauce, vinegar, ginger and cloves. Pour over pork. Cover and cook on low for 4-5 hours or until a meat thermometer reads 160°F.
Remove meat and onions from slow cooker; keep warm. Discard bay leaves. In a small bowl, combine cornstarch and cold water until smooth. Gradually stir into slow cooker. Cover and cook on high for 30 minutes or until thickened, stirring twice.
Slice pork; top with onions, sauce and sesame seeds. Serve on a bed of rice if desired.