Preserving the History and Future of Heirloom Corn at Sobre Masa

Zack and Diana Wangeman, the founders of Brooklyn tortilleria and restaurant Sobre Masa, discuss mastering the art of nixtamalization and celebrating the beauty of heirloom corn.

There are 59 recognized varieties of heirloom corn native to Mexico, each with different characteristics and purposes. The grain was domesticated in the region around 10,000 years ago, and these 59 breeds have developed and evolved to suit the microclimates of their native territories and the tastes of the communities that cultivated them. In Tlaxcala and Mexico City, for example, the large, starchy grains of cacahuazintle corn are prized for pozole, while in Oaxaca, dense bolita corn is used to create firm, pliable masa for large tlayudas. 

Despite this incredible diversity, most mass-produced tortillas are made with only a few varieties of yellow and white corn, and the majority of corn grown in the U.S. is a hybrid of just two breeds. In recent years, however, a growing movement around Mexican heirloom corn has emerged, with a new generation of chefs and importers working to celebrate and preserve landrace corn varieties, independent farms, and indigenous farming practices. 

In Brooklyn, Sobre Masa, a tortilleria and restaurant in Bushwick, is leading the charge. Founded by Chef Zack Wangeman and his wife Diana, who were both raised in Oaxaca, Sobre Masa is the first tortilleria in NYC to use solely imported Mexican heirloom corn. “There’s a really strong community in Mexico that is trying to promote and preserve heirloom corn,” says Zack. “So our idea evolved from making tortillas in New York to figuring out how we could be a voice for that community in the city.”

After many years working as a pastry chef in some of the country's most prestigious restaurants (including at Per Se in New York and Meadowood in California), Zack pivoted to hosting Mexican pop-ups in 2018 as a way to make the dishes and quality tortillas that he missed from his youth. “Sobre Masa really came out of nostalgia and not being able to find good tortillas in New York,” he says. 

This sent him down a tortilla-making rabbit hole. “It took me down this obsessive path to try and understand nixtamalization and corn — its culture, its community, and all the people around it,” he remembers. Traditional corn tortillas only contain three ingredients: corn, water, and the mineral lime — usually as calcium hydroxide — but making the dough, called masa, is a precise and labor-intensive endeavor. Before the corn is ground into maize, it is treated using an ancient process called nixtamalization, which involves cooking the kernels in lime water and then soaking them in the liquid overnight (or longer, depending on the corn variety). This works to break down the starches in the corn to give the dough more elasticity, as well as making the nutrients in the grains more bioavailable, so they are better absorbed by your digestive system. 

To perfect his techniques, Zack turned to his connections back home in Oaxaca, including his (then) high school friend Diana and her family, who run a successful Zapotec restaurant in Teotitlan del Valle just outside of Oaxaca City. Over the course of a couple of years, he honed his nixtamalization methods, developed new recipes, and started serving tacos and other Oaxacan specialties while running the kitchen at the now-closed Carroll Gardens pub Folksbier. During that time, he also became enamored with the amazing variety and specific uses for heirloom corn. 

“Sin maíz, no hay país” (“without corn, there is no country”) is a common saying and a recent rallying cry for the protection of native corn in Mexico. The grain, which has been cultivated in Mesoamerica for thousands of years, provided the foundation for indigenous civilizations in the region and even plays a key role in the Mayan Creation story, Popol Vuh. Traditional farming techniques involved selecting, saving, and sharing seeds from one season to the next, which increased genetic diversity and allowed certain varieties to evolve and adapt to a range of different climates and elevations. 

These ancient corn varieties were also bred to suit the palates of local communities, and so most regional Mexican dishes are tied to a specific landrace of corn. “Where Diana’s from, for example, they use bolita corn because Oaxacan food is so saucy and they like their tortillas to have a little bit more resistance,” Zack explains. “So they’re a lot harder than in, say, Tlaxcala where they like those really soft, pillowy tortillas.” 

But since the Green Revolution of the 1940s–1960s, and later, the enactment of the North American Free Trade Agreement in 1994, these native heirloom corn varieties have begun to decline, as Mexican farmers were encouraged to farm hybrid seeds while corn from the United States flooded the market. Now, Mexico imports 16 million tons of corn from the USA per year — a trend that threatens the heritage and culture of regional Mexican cuisine, as well as encouraging a genetic uniformity that could reduce corn’s ability to adapt to a changing climate. 

“We encourage people to use as many different kinds as possible. Every parent has their favorite kid, of course, but we're trying to showcase the diversity.”

— Zack Wangeman, Chef and Cofounder of Sobre Masa

To combat this, a group of new distributors, including  Tamoa — which supplies Zack and Diana at Sobre Masa — are working to bridge the gap between Mexico’s two million small corn farms and the chefs who understand the magic of heirloom varieties. “It’s cool to see this growing community that’s just as driven, and we all share the same values,” says Zack of the collaboration. Based out of Mexico City, Tamoa works with a network of small, heirloom corn farmers to buy their surplus grains and distribute it to chefs all around Mexico, the United States, and beyond. This arrangement allows farmers to monetize their crops, while also saving enough to feed themselves and their communities. 

Zack officially moved into Sobre Masa’s current (and first permanent) location in late 2020. The pandemic gave him some downtime to regroup for the launch, and he invited Diana, who was then still living in Mexico, to help him open the space. Together, they made a plan for the tortilleria and developed the menu for the restaurant, and in the process, they fell in love. Diana and Zack got married in July 2021, and they opened the doors to Sobre Masa on Bushwick’s Harrison Place in October of that year. 

The space is designed to give corn — and the tortilla-making process — a starring role. In the front, there is a coffee bar that uses beans that Diana and Zack get from friends back home, as well as a counter serving Mexican sweets, and of course, fresh tortillas. Walking in further, you pass the tortilleria, where you can watch Zack and Diana’s team grinding the corn, kneading the masa, and cooking the tortillas — filling the space with a rich and sweet aroma. Then, behind the tortilleria, you’ll find the restaurant, where Diana and Zack serve a range of tortilla-based dishes, like tacos, gringas and enchiladas, plus cocktails using Mexican spirits. 

They have also started selling their tortillas and masa to shops and restaurants in NYC, including Colonia Verde, La Loncheria, ABC Cocina, and of course, Eleven Madison Park. Each batch has its own unique characteristics, based on the corn, but they are all deliciously soft, nutty, pliable, and just thick enough to hold a generous amount of filling. “We encourage people to use as many different kinds as possible,” says Zack. “Every parent has their favorite kid, of course, but we’re trying to showcase that diversity.” 

At EMP, we use masa from Sobre Masa in our menu each season in at least one dish. On our winter 2025 menu, for example, you can find Zack and Diana’s white masa in the fried butternut squash course.

Fried Butternut Squash with Shiso and Spinach - Winter 2025