The basic surroundings here belie an elevated menu that goes beyond the usual tacos and enchiladas. The chile relleno pleased us with its ground beef stuffing and mild roasted pepper. But the real star was a chicken breast topped with a sweet, tangy cilantro-and-tamarind sauce and garnished with nuggets of tart queso fresco. We also give a nod to the guacamole, seasoned with a hint of garlic, but pass on the thick chips and runny salsa and save room for the house specialties.