Huitlacoche is the fungal, culinary delicacy Ustilago maydis that grows on ears of corn. Inhabitants of Mexico and indigenous people from the Southwestern United States enjoy this rich, smoky ingredient in foods like tamales, soups, quesadillas, appetizers, and ice cream. While farmers treat huitlacoche as an infectious affliction that ruins corn crops, it has a long history in the cuisine of Aztecs, Hopi, and Zuni.
The word huitlacoche, pronounced whee-tla-KO-cheh, comes from two words in Nahuatl, the language of ancient Aztecs occupying the area that became Mexico. "Huitlatl" means excrement and "coche" means raven. Europeans have tried to rename what they consider a grotesque word to popularize the unusual fungus by calling it Mexican Truffle, Aztec Caviar, or Maize Mushroom. Yet huitlacoche remains a regional specialty because it is best fresh, but has also been canned or frozen for export.
Huitlacoche, also spelled cuitlacoche, remains fairly rare because it appears on ears of corn as they ripen after a heavy rain or period of high moisture. Some farmers are experimenting with purposefully cultivating it, but they have not had a lot of success. The fungus resembles grey or silver dry bulbs inside the ears along normal kernels. Once the kernels are "infected," they will swell slightly and turn darker shades of grey as the spores grow. Huitlacoche can be harvested just as you would harvest unaffected corn kernels.
When fresh, the spongy nubs are cooked with other strongly flavored ingredients such as chile and garlic. Over heat, the huitlacoche leaks an inky liquid, turning the mixture black, and gradually cooks down to a puree. It can also be sauteed in butter or oil. Although farmers desiring uninfected corn disparage the fungal growth as smut, soot, or devil's corn, the Hopi call it nanha and the Cochiti call it wesa. These tribes revere its delicate taste and powerful life-giving properties. It transforms stews, tamales, and quesadillas with a rich, earthy, and pungent flavor.