Labor will be Shake Shack's greatest headwind for the next couple of years, said CEO Randy Garutti.
"There's no doubt. With rising minimum wage, the amount that we're growing — we announced we're going to have our largest year of growth yet — and with that comes a lot of preparation and a lot of leadership we've got to develop," Garutti told CNBC's "Fast Money" on Monday.
The country is moving toward $15 minimum wage, he said, and Shake Shake is experimenting with ways to pay its team while also having a solid business model. The burger chain is testing a cashless kiosk in New York that it opened last month. Employees at the location are paid a minimum of $15 per hour.
Shake Shack is also toying with its menu. It unveiled chili last month that will be available for a limited time. The restaurant typically keeps a tight menu, Garutti said, but sometimes it likes to add things.
"I think it's going to be a winner," he said.
Shake Shack's same-store sales decreased 1.6 percent last quarter. Garutti defended the chain's strategy of sometimes opening stores nearby other ones. He said there are some instances where putting a restaurant near another one may have hurt sales, but that's a decision management will make "time after time."
"We're not running this business for percentages," Garutti said. "We're running it to make a lot of money, and we do that when we open more Shacks."