Spray a 3 or 4 quart slow cooker with cooking spray; place ribs, onions and garlic in cooker.
Cover; cook on low setting for 8 to 9 hours.
About 10 minutes before serving, remove ribs from slow cooker; place on serving platter and cover to keep warm.
In 2 cup microwave safe measuring cup, combine all sauce ingredients; mix well.
Stir in 3/4 cup juices from slow cooker; discard remaining juices.
Microwave sauce on high for 2 to 2 1/2 minutes or until mixture boils and thickens, stirring once halfway through cooking.
Pour sauce over ribs. To make them a bit sticky, I do it one of two ways depending on time. You can either drain all the grease from the crock pot and add the ribs and the sauce back to it, then cook on high uncovered for about another hour or if pressed for time, you can transfer the sauce covered ribs to a shallow baking pan and caramelize under the broiler, basting frequently.
(I can personally think of all sorts of things I might try adding to this, but until I have tried them out, I will wait to post them lol. Let me know how it turns out!).