An upscale shopping enclave might be the last place you'd expect blistering sabor genuine Latin flavor but that's just what shines through the cooking at Tacubaya, Fourth Street's glorified taco stall. The restaurant's pretty palette of dahlia pinks is slick enough to make you suspect its cred, but on recent visits the food showing up at our tables was homestyle tasty. A taco al pastor's blackened, spit-roasted pork shards flaunted an authentic air of the rustic, and its pureed avocado-and-raw-tomatillo salsa breathed mintlike freshness. Cubes of braised tongue in a taco de lengua were like wet velvet, and a roasted tomatillo salsa had a razor-sharp vegetal tartness at $3.25, these were more than twice the cost of truck tacos, but worth every dime. Concentrated and chewy, a sope of corn masa had a fantastic filling of chorizo, potatoes, and pickled vegetables. Even the brownielike Scharffen Berger chocolate cake buzzed with cinnamon and chile in an authentically revelatory way.