Combine bbq sauce, brown sugar, cider vinegar, oregano, Worcestershire sauce, cayenne pepper, and chili powder in a small bowl.
Salt and pepper the ribs. Place ribs in slow cooker, and cover in sauce. Cook low and slow for eight hours or high for four hours.
After the ribs are done, spoon the bbq sauce in the slow cooker over the ribs before removing. Cut the ribs, serve with bbq sauce.