A Shake Shack employee, center, gestures as she speaks with a customer, left, at the counter inside the company's new burger restaurant in London, U.K., on Tuesday, July 2, 2013. Shake Shack, opening in London's Covent Garden this week, started as a hotdog cart in New York's Madison Square Park, and has outlets in six U.S. states as well as in the Middle East and Turkey. Photographer: Simon Dawson/Bloomberg via Getty Images