Two all-chicken patties, special sauce, lettuce, cheese ... After years of it being available overseas, McDonald's is finally bringing the Chicken Big Mac to the U.S. It will be hitting locations across the country on October 10th but will only be around for a limited time. The Chicken Big Mac substitutes the original version's two beef patties with two tempura-battered chicken patties and keeps the standard lettuce, cheese, pickles and special sauce on a triple-bun stack.