The word huitlacoche comes from the Nahuatl language and means "excrement of raven."
Huitlacoche appears on corn after heavy rain or high moisture after the ears have ripened. The grey, spongy growths are called "galls" and contain black, inky spores. When the galls are cooked, the dark color is released in the food. Huitlacoche is said to have a smoky, earthy flavor and is often cooked with chiles and is enjoyed in soups, tamales, and quesadillas. Since there is a demand for it, farmers have tried to grow it commercially, but without success. Huitlacoche is best enjoyed fresh, and for this reason, it is considered a local specialty as it doesn't travel well. It is canned and sold in Mexican markets and online.
If you have access to fresh corn crops, you may be able to get fresh huitlacoche. Should you find some ears with the spongy, gray galls on them, here's how you prepare them. Carefully pull the husks away from the ear of corn and remove the corn silk. Using a sharp knife, cut the corn kernels with the huitlacoche from the cob lengthwise. Chop them up and add to recipes. Here are a few to try:
Related: Word of Mouth: Huitlacoche