McDonald’s is having an identity crisis.

For years, it has lurched from showcasing new items — salads! Egg White Delight McMuffins! sliced apples! — to mining nostalgia for its basic Big Macs and fries. Its core customers still line up at the drive-through window for cheap, quick cups of coffee and hash browns. But the company is also trying to appeal to more finicky eaters who have moved onto upstart competitors like Smashburger and Chipotle, which market their quality ingredients and food customization.

Can McDonald’s be both fast and bespoke? Cheap and high-quality?

Steve Easterbrook seems to think so. Mr. Easterbrook took over as the chief executive of McDonald’s on March 1, and last week he was in Las Vegas, where the company presented franchisees and suppliers with a new vision of McDonald’s. That “destination,” as it was called, was McDonald’s as “a modern, progressive burger and breakfast restaurant” where “customization and made to order” are essential and where executives “align our food story around the consumer’s definition of quality and value.”

By Tuesday, when the meeting started, he was realigning the company’s food story. Mr. Easterbrook’s first major act as C.E.O. was to announce that within two years all the chicken served at its restaurants would be free of antibiotics, or at least those antibiotics also used in humans. It was a big move for McDonald’s, which is one of the biggest buyers of chicken, and one that pleased health officials who see overuse of antibiotics in animal husbandry — and the resulting antibiotic-resistant strains of bacteria — as a serious threat to human health.