After more than half a century in business, this taqueria, with just enough room for a handful of diners to stand at its counter, has earned is place in Mexico City's taco pantheon. Its signature creation, the Gaonera taco features thinly sliced beef filet, seared to order and seasoned simply with salt and lime, cooked alongside fresh corn tortillas. A handful of other options, including chuleta (pork chop) and costilla (beef rib) are likewise worth considering, and a duo of excellent house-made salsas make for fine accompaniments.