Mix together chicken, ketchup, bread crumbs, and mustard. Form the mixture into four 1/2 inch thick patties. Heat a cooking spray coated frying pan over medium heat and cook each patty 4 minutes per side or until preferred degree of doneness.
Top each burger with cheddar cheese, place lid on pan, and cook until cheese is melted. Arrange burgers in rolls with bacon, lettuce, tomato, and onion.