Tulcingo del Valle, on 10th Avenue between 46th and 47th Streets, makes a full range of Mexican classics, but I can only speak to their tacos. Three soft tacos come to an order, with double-layered tortillas for maximum stability, but beware of the strange rules for ordering. You can't order three different types; they've got to be two of one variety and one of the other, or all three the same. On top of that, certain fillings like chorizo and al pastor must be ordered by the pair. Despite these nonsense restrictions, our waitress was very friendly as she guided me to an acceptable combination of 1 carne asada and 2 al pastor tacos ($10.50).
Each taco comes with a healthy amount of meat, topped with chopped onions, cilantro, guacamole and a spicy salsa verde, with more on the side to be applied as needed. Also on the side come lime wedges and sliced radishes. While the carne asada was decent, I was a bigger fan of the al pastor, which had bits of pork grilled to a crisp, foffset by tender little cubes of pineapple. Skip the chips and guacamole ($5.95), which was bland, lacking both heat and salt.