Vasco is Spanish for “Basque,” but dinner at this Chelsea staple is usually a Maine event—fresh, reasonably priced New England lobster. Scribbled on the waiter’s notepad is the latest by-the-pound list of available crustaceans living out their final moments in the kitchen’s tank. Go classic—simply boiled and served with drawn butter—or try Francisco’s Favorite: a 1-pound lobster stuffed with crabmeat and sprinkled with queso fresco. The simple formula appears to be working: So many people line up to get into the dark, dated dining room, the maître d’ occasionally resorts to using a velvet rope.