Taco de Nopales con Queso

The filling of this taco is a cactus, the flat green paddle of the prickly pear, the same plant the founding eagle of Mexico stands on at the center of the national flag. Stripped of its spines, sliced into strips, charred on a comal, and folded into a warm corn tortilla, the nopal is one of the oldest things a Mexican kitchen puts inside a tortilla. It is also one of the leanest, a wild green vegetable that brings almost no richness of its own to the bite, which is where the cheese comes in.

The cheese is the recent guest, and it is the half of the name doing the structural work. On its own the grilled paddle is lean and sharply sour, a tart green thing that eats more like a vegetable side than a meal. A fistful of crumbled queso fresco is the soft salty weight that answers it, cool against the heat and rich against the sourness, turning two thin slivers of cactus into a bite worth folding into a tortilla. Drop the cheese and you have a markedly more austere taco; keep it and the paddle reads as lunch.

Before any of that, the paddle has to be disarmed. A raw nopal carries fine glochids and spines that have to be scraped off with a knife blade run against the grain, the edges trimmed, the pad rinsed. Skip it and the filling is inedible; do it carelessly and a stray glochid finds a lip. The cleaned paddle is then sliced, and how it is cooked decides everything about the texture, because a nopal holds a clear viscous sap the kitchens call baba, and raw or boiled it turns the filling slick and rope-like in a way few first-time eaters forgive.

Grilling is the fix, and it is the move that makes this taco work. Laid on a hot comal or grill, sliced thin so the heat reaches every surface, the strips release their baba as steam and tighten as the edges char and blister. The slime cooks off, the paddle firms to a snap-tender bite somewhere between green bean and bell pepper, and a faint sourness deepens under the smoke. The same paddle simmered in water would weep its sap into the pot and arrive limp and gluey. On the grill it loses the slick and keeps the tartness, which is exactly the trade the taco is built on.

Build it and the parts answer each other in the hand. The warm corn tortilla goes down first, then the hot charred strips, then a fistful of cool queso fresco that begins to soften against the heat without melting, raw onion for bite, cilantro for lift, a spoon of salsa to carry it. The first taste is smoke and a green vegetal tartness, the cheese arriving salty and crumbling, the onion sharp underneath. It eats clean and a little austere, a taco with no fat in it but the cheese, and the lime squeezed over the top pulls the sourness forward rather than cutting it.

It sits inside the broad family of vegetable and cheese tacos that fill the meatless end of a Mexican menu, and its closest neighbors are instructive. A plain taco de nopales drops the cheese and leans harder on chile and onion; a quesadilla de nopales seals the same paddle inside a folded tortilla with melting cheese over a flame, which is a different sandwich with a closed top rather than an open one. The cheese here is crumbled and cool, not melted, so the nopal stays the lead and the queso stays the counterweight. None of these is a lesser taco for having no meat. The cactus is the point, and the cheese is what makes a lean wild vegetable into a meal.

The Plant at the Center of the Flag

The nopal carries no founding cook and no first date, because it was being eaten on this land for thousands of years before anyone arrived to record it. The Nahuatl word nochtli names the prickly pear, and the Mexica capital took its name from the plant: Tenochtitlan, the city beneath modern Mexico City, is read as the place of the prickly-pear cactus growing on stone. When the friar Bernardino de Sahagún set down the natural history of the Nahua world in the Florentine Codex around 1577, the nopal and its many tunas already filled the pages, the paddle long established across Mesoamerica as food, medicine, and host to the cochineal dye insect. The founding legend fixes the plant in the same place: the Mexica were told by their god Huitzilopochtli to settle where an eagle stood on a nopal with a serpent in its beak, and the sign was read on an islet in Lake Texcoco in 1325, the year given for the city's founding. That eagle, that serpent, and that cactus are the coat of arms at the center of the Mexican flag today, which is, as far as historians can tell, the only national flag in the world built around a plant.

The cheese is the late arrival, and it marks the one datable seam in the dish. Cattle and the milk to make fresh cheese reached this land with the Spanish, who took Tenochtitlan in 1521, so the queso fresco crumbled over the paddle is a colonial import laid across a pre-Columbian vegetable. The taco de nopales con queso is that meeting held in one tortilla: the plant from the 1325 founding of the city, the cheese from the conquest that ended it almost two centuries later, eaten together off a comal that would recognize only half of what it holds.