Where should the boss take you for lunch on your first day on the job? Katz’s Deli, of course. Mayor de Blasio and his wife, Chirlane McCray, treated Richard Carranza, New York City’s new schools chancellor, to a pastrami sandwich at the famed Lower East Side deli. That’s Katz’s owner, Jake Dell, giving Carranza a New York welcome. The mayor has been known to drop in at the Ludlow Street landmark from time to time. According to the Post, the mayor’s photo is missing from the wall at Katz’s because it was damaged.