Combine beef, egg, garlic, cheese, bacon, bread crumbs, onion, Worcestershire sauce and rosemary in bowl.
Divide meat into 6 portions. Form into 3/4 inch (2 cm) thick patties. Make thumb-print depression in centre of each patty (to prevent rounding while they grill). Make Ahead: Refrigerate, covered, for 1 hour or up to 1 day.
Grill over medium heat on preheated, oiled grill for 5 to 7 minutes per side, testing doneness with a digital instant read thermometer inserted sideways into centre of each patty to ensure patties are cooked to 160°F (71°C).