Spray slow cooker with non-stick cooking spray. Place ribs in cooker, salt and pepper to taste. Cover with onions and barbecue sauce. If needed due to amount of ribs, you can layer them, adding the ribs, onion and barbecue sauce in two layers. Cook on low for *6 to 8 hours, until pork is tender. When ready, remove from cooker and place on baking sheet or roasting pan. Baste ribs with fresh barbecue sauce and place under broiler for a few minutes, until the barbecue sauce starts to bubble and caramelize. Serve with your favorite sides. Enjoy!