We think of Casa Vallés as a time capsule, since little about it seems to have changed since it opened in 1942. The ground-level tapas bar has ignored the pintxos creativos craze that’s swept the rest of the city. This is where you come for a bite of tortilla Española (potato omelet), a casserole of pork-veal meatballs, or a plate of canned anchovies laid out solemnly on a plate. The restaurant upstairs is spare and features old-fashioned wood paneling on the walls. The kitchen keeps it simple: grilled fish, veal, pork, chicken. The oven-roasted spider crab is exceptional, and many locals stream here for the Madrid-style tripe.