Tlayuda con Chapulines y Aguacate

This is Oaxaca's dish. Not Mexico City's reinterpretation of it, not a "Mexican pizza," not a novelty for tourists to photograph at the Mercado 20 de Noviembre. The tlayuda is a working food from the Valles Centrales, and it has been feeding Oaxacans for longer than anyone has been writing about it.

The foundation is the tortilla itself, a 12-to-14-inch round of nixtamalized masa, partially dried on a comal so it develops that leathery stiffness that holds everything on top without collapsing. Then asiento, the dark, grainy sediment from the bottom of the pork-rendering cazo, spread across the surface the way you would butter bread if butter tasted like smoke and pork fat. Then the black beans, fried with avocado leaf until they hold their shape on a spoon. Then quesillo, pulled into strings, because that's how quesillo works. Everything that follows is the cook's signature.

Chapulines are not a garnish. In Oaxaca they are an ingredient, sold by the kilo at the mercado, sorted by size, seasoned with garlic, lime, and chile, and eaten the way the rest of the country eats peanuts. On a tlayuda, they bring a dry crunch and a toasty, earthy protein that no meat replicates. The chile de agua, Oaxaca's own fresh green chile, roasted and stripped into ribbons, gives a vegetal heat that belongs here because it grows here. And the avocado is just ripe avocado, sliced and laid on top where it can cool the whole thing down.

I have eaten tlayudas at midnight on the street in Oaxaca City, standing next to a comal balanced on a metal drum, watching a senora build them with the speed of someone who has done this ten thousand times. Her hands moved through asiento, beans, cheese, chapulines without looking, the way a pianist reads music. I asked her for proportions. She looked at me like I had asked her how many breaths she takes per minute. Recetas probadas y garantizadas, but some recipes live in the hands, not on the page.