Give a man a slider, and he’ll instantly need a dozen more. Teach a man to make sliders, and you’ll make him the most popular guy on the block.At least that’s the expectation at the new Spy Diner, a sidewalk food cart from the team behind Zola and D.C. Central Kitchen.Greet the day with homemade coffee cake or egg-and-cheese sammies (served solo or topped with pork, ham, or bacon).Later, the menu turns to sliders with a menagerie of offerings (sourced mostly from local farms). Choose from lamb and goat cheese, roast beef with caramelized onions and horseradish, BBQ pork and coleslaw, vegetarian-friendly tomato and Brie, or old-fashioned beef patties. Daily soups wash it all down.The cart functions as a training center for graduates of D.C. Central Kitchen, which trains unemployed and homeless adults for careers in food service.We spy a success.Spy Diner, 9th and F Streets NW. Mon.-Fri., 8:30 a.m.-5:30 p.m.; Sat. & Sun., 11 a.m.-6 p.m.