An ancient process has been making a comeback in the kitchens of some of Houston’s most innovative restaurants. Bayou City chefs are reintroducing nixtamalization, a centuries-old method once used by the Aztecs and Mayans, offering a delicious alternative to the mass-produced tortillas commonly found in stores and restaurants. Nixtamalized tortillas come in a variety of hues, including blue, green and deep yellow, and are used as vehicles to serve delicious and often authentic Mexican dishes. But has this ancient process and the tasty tortillas that come with it caught on with Houston diners? What is nixtamalization? …