In a bowl, add the garlic, Worcestershire sauce, brown sugar, smoked paprika, ground coriander, ½ cup barbecue sauce, salt, and pepper. Use a spoon to mix it together until it’s well combined.
Cut the rack of ribs in half so that it can fit into the slow cooker, then brush all over to make sure they are coated in the sauce, and pour the sauce over the ribs. Put the slow cooker on LOW for 5–6 hours.
Preheat the oven to 400ºF and line a baking tray with parchment paper. Once the ribs are cooked and the meat is soft and falling off the bone, carefully lift the ribs out and place them onto the lined baking sheet.