Last fall, I gave a talk on the history of tacos at Texas State University, in San Marcos, a city about thirty minutes south of Austin. A professor sent me off afterward with a gift bag, which contained the usual school-logoed T-shirts, pens, and coffee mugs, but also something better: three bags of flour tortillas. They were unlike any I had ever seen: each one thick as a magazine, and whiter than Wonder Bread. They were made by La Paloma White Wings, of San Antonio, a brand ubiquitous in Texas and nowhere else. On my flight back home to Southern California, I opened a pack and rolled one up. Many Mexicans consider eating tortillas cold a waste, like using Veuve Clicquot for mouthwash. You need to warm them to unlock their flavor, their elasticity. But I couldn’t help myself. I ate three, each one buttery, like a chewy biscuit. When I got home, I made a sublime quesadilla, then posted a photo of the La Paloma packs on Instagram. In response, I received hundreds of likes, along with requests on where to find them (the company ships). But then a friend from Houston who grew up in Mexico chimed in: “Fat thick torts are puro Tex-Mex,” he wrote. “Gross.”

Few foods are more contentious among Mexicans than the flour tortilla. People rhapsodize about the earthiness of a corn one hecho a mano (freshly handmade); high-end Mexican restaurants in the United States boast on social media about their use of heritage maize to create organic, non-G.M.O. versions. The corn tortilla is an easy symbol of pride, an elemental food that connects Mexicans to our indigenous past and ancestral homeland. Those made de harina (of flour), by contrast, are bastard children of the U.S.-Mexico borderlands, a hybrid of the corn flatbread that has existed in Mexico for thousands of years and the wheat that the Spanish conquistadors brought over. Recent Mexican immigrants deride flour tortillas as a gringo quirk. (My own mother had never even tasted one until she arrived in Southern California from central Mexico, during the late nineteen-sixties.) Foodie purists dismiss them as not “real” Mexican food. The authors of the excellent cookbook “Decolonize Your Diet” offer recipes for tortillas made with the flour of amaranth and mesquite but reject the bleached-wheat version used in most flour tortillas as “a product of colonization.” They’re even losing ground in the American mainstream. In 1993, the Tortilla Industry Association (TIA) estimated that flour tortillas captured sixty per cent of the U.S. market, while corn got forty per cent. By 2015, according to TIA, corn was only a smidge behind, accounting for $5.8 billion, compared to flour’s $5.9 billion.

I suspect that flour tortillas get so little respect, in part, because the standard version that most people know Stateside, the ones wrapped around Chipotle burritos, folded to make Taco Bell quesadillas, or pinched into breakfast tacos at the latest hipster hot spot, are so bland. The most popular brands—Mission and Calidad, subsidiaries of Gruma, the largest tortilla company in the world—too often stick on comales and turn into clammy muck once they enter your mouth. They taste like the industrial-scale process from which they come: metallic, rushed, with no soul. If you live or travel in the borderlands, though, you quickly learn that great flour tortillas do exist, and can be revelatory. Like good corn tortillas in Mexico, Southwestern flour tortillas vary from state to state. They are products of the long-standing Mexican-American communities who have proudly made and eaten them despite scorn from all sides. They are, in that sense, the Mexicans of Mexican food.

Texas tortillas, which are often made with baking powder, get flaky and tend to puff up like Indian roti bread when made fresh. Those in New Mexico and southern Colorado taste wheatier; some food historians think that they’re a remnant of the crypto-Jews and Muslims who settled the area in the seventeenth century. Until recently, Southern California’s contribution was mostly chalky and forgettable; at home, my mom used Guerrero flour tortillas (Gruma’s brand for the Latino market) only for the lunch burritos I’d take to school. The trend for young, middle-class Mexican-Americans in Southern California today is to seek artisan flour tortillas de agua, prepped in the airy, translucent style of the Mexican state of Sonora, with only flour, water, and salt.

The American capital of flour tortillas, though, is Arizona, where they are prepared in a manner virtually identical to that of the ones across the border in Sonora. In Arizona, you can find versions as small as a palm or wider than a basketball hoop. No matter the size, they’re surprisingly sturdy and versatile in ways that their U.S. peers aren’t. Fold one up, and you get what Arizonans call a burro and the rest of the world calls a burrito; dunk a burro in the fryer, and it becomes a chimichanga. Bake the bigger tortillas with cheese and meat, and they transform into what’s known as a cheese crisp.

These are the native tortillas of Steven Alvarez, a professor of English at St. John’s University in Queens, who’s teaching a senior seminar this semester titled “Taco Literacy: Writing Transnational Mexican Foodways.” Alvarez, who hails from the Arizona mining town of Safford, remembers his mom making fresh flour tortillas every weekend. He’d help to mold the dough into little balls that she would then roll out before placing them on the comal. For him, flour tortillas are about his own family memory, and nostalgia. But they are also no less a part of Mexican culinary heritage than chiles or maize. “There has been a resurgence in the turn toward the indigenous, pre-Columbian roots of Mexican food,” Alvarez told me. “But, no doubt, what we understand as Mexican food today would not be the same without pork, chicken, beef, cheese, and flour—all introduced by the Europeans.”

Every time Alvarez visits home, he returns to New York with at least seven dozen-count packs of flour tortillas from Mi Casa Tortilla Factory, which serves Safford and the towns in the surrounding Gila Valley. “I freeze them,” he said. “But they never seem to last long enough.”