Ever wondered what's on a Big Mac®? The McDonald's Big Mac® is a 100% beef burger with a taste like no other. The mouthwatering perfection starts with two 100% pure all beef patties and Big Mac® sauce sandwiched between a sesame seed bun. It’s topped off with pickles, crisp shredded lettuce, finely chopped onion, and a slice of American cheese. It contains no artificial flavors, preservatives, or added colors from artificial sources.