Mexican Truffle or Mexican Corn Truffle (huitlacoche or corn smut)

Huitlacoche (also spelled “cuitlacoche”) is a corn fungus (corn smut) that has long been popular in Mexican cuisine. In the 1980s, huitlacoche began to be introduced into American “Mexican” and “Tex-Mex” restaurants. Huitlacoche has been called the “Mexican truffle” (or “Mexican corn truffle”) to highlight its appeal to refined culinary tastes.
 
In 1989, a dinner at the James Beard House in New York City (catered by Josefina Howard of the Rosa Mexicano restaurant) featured huitlacoche and other Mexican foods. Huitlacoche was promoted as the “Mexican truffle” at this dinner, in an effort to get Americans to try the unfamiliar food. The name “Mexican truffle” wasn’t coined at this dinner, however—“Mexican truffle” is cited in print in the 1988 Los Angeles (CA) Times.
 
Huitlacoche is also (less frequently) known as “Mexican caviar.”
   
   
Cooks Recipes - Cooking Dictionary
Huitlacoche [wee-tlah-KOH-cheh] - (also spelled cuitlacoche; also referred to as “Mexican corn truffle”) is a fungus which grows naturally on ears of corn (Ustilago maydis). The fungus is harvested and treated as a delicacy. The earthy and somewhat smoky fungus is used to flavor quesadillas, tamales, soups and other specialty dishes.
   
GourmetSleuth
Huitlacoche [wee-tlah-KOH-cheh]
Mexican Corn Truffle
Huitlacoche (also spelled cuitlacoche) is a fungus which grows naturally on ears of corn (Ustilago maydis).  The fungus is harvested and treated as a delicacy.  The earthy and somewhat smoky fungus is used to flavor quesadillas, tamales, soups and other specialty dishes.
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According to Betty Fussell in her book The Story of Corn, the Hopi call the corn fungus nanha and collect when it is young and tender, par boil it for 10 minutes then sautéd in butter until crisp. 
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Another interesting story told by Ms. Fussell is that of a dinner presented by the James Beard House in New York City in 1989.  The purpose was to give Americans a tasting of the corn smut but with a new name “Mexican Truffle”.  The menu was created by Josefina Howard of Rosa Mexicano restaurant and included huitlacoche appetizers, soup, crepes, tortilla torte, and even an huitlacoche ice cream.
 
The Free Dictionary
Mexican truffle
n.
See cuitlacoche.
The American Heritage® Dictionary of the English Language, Fourth Edition copyright ©2000 by Houghton Mifflin Company. Updated in 2003.
 
Wikipedia: Corn smut
Corn smut is a disease of maize caused by the pathogenic plant fungus Ustilago maydis. U. maydis causes smut disease on maize (Zea mays) and teosinte (Euchlena mexicana). Although it can infect any part of the plant it usually enters the ovaries and replaces the normal kernels of the cobs with large distorted tumors analogous to mushrooms. These tumors, or “galls”, are made up of much-enlarged cells of the infected plant, fungal threads, and blue-black spores. The spores give the cob a burned, scorched appearance. The name Ustilago comes from the Latin word ustilare (to burn).
 
Considered a pest in most of the United States, smut feeds off the corn plant and decreases the yield. Usually smut-infected crops are destroyed. Some farmers may also choose to prepare corn silage out of the smutted corn. However, in Mexico corn smut is called huitlacoche (IPA: [wit͡ɬakot͡ɕe], sometimes spelled cuitlacoche), a Nahuatl word reportedly meaning raven’s excrement. It is considered a delicacy, even being preserved and sold for a higher price than corn. For culinary use, the galls are harvested while still immature — fully mature galls are dry and almost entirely spore-filled. The immature galls, gathered two to three weeks after an ear of corn is infected, still retain moisture and, when cooked, have a flavor described as mushroom-like, sweet, savory, woody, and earthy. Flavor compounds include sotolon and vanillin, as well as the sugar glucose.
 
The fungus has had difficulty entering into the American and European diets as most farmers see it as blight, despite attempts by government and high profile chefs. In the mid-1990s and due to demand created by high-end restaurants, Pennsylvania and Florida farms were allowed by the United States Department of Agriculture (USDA) to intentionally infect corn with huitlacoche. Most observers consider the program to have had little impact, although the initiative is still in progress. Regardless, the cursory show of interest is significant because the USDA has spent a considerable amount of time and money trying to eradicate huitlacoche in the United States. Moreover, in 1989 the James Beard Foundation held a high-profile huitlacoche dinner. This dinner famously tried to get Americans to eat more of it by renaming it the Mexican truffle.
   
Wikipedia: Truffle (fungi)
A truffle (IPA: /ˈtrʌfəl̩/) is a fungal fruiting body that develops underground and relies on mycophagy for spore dispersal. Almost all truffles are ectomycorrhizal and are therefore usually found in close association with trees.
 
There are hundreds of species of truffles, but the fruiting body of some (mostly in the genus Tuber) are highly prized as a food. Brillat-Savarin called these truffles “the diamond of the kitchen”. Edible truffles are held in high esteem in French, northern Italian and Istrian cooking, as well as in international haute cuisine.
   
31 March 1988, Los Angeles (CA) Times, “Guadalajara Grill” (restaurant review) by David Nelson, Metro, section 2, pg. 12:
The dish called queso cuitlacoche sounds promising because it includes the savory corn fungus (cuitlacoche) that some regard as a Mexican truffle, and of which the Tijuana restaurant makes an extraordinary cream soup.
 
20 March 1990, Chicago (IL) Daily Herald, “One man’s delicacy is another farmer’s pest” (UPI), section 2, pg. 5, col. 1:
ATLANTIC CITY, N.J.—Yuppie diners in nouvelle cuisine restaurants are paying big bucks for a taste of the maize mushroom also known as the Mexican truffle or huitlacoche.
 
The earthy, smoky-flavored mushroom has been described as “Mexican caviar” and as titillating to the palate as the coveted European truffle.
     
Google Books
US/Mexico Business
Published by Hemisphere Publishers’ Group, 1997
Item notes: v. 4, nos. 1-10
Pg. 12:
And it’s meant pushing Texans to try huitlacoche, described as an “exotic Mexican truffle,” instead of the typical Tex-Mex fare.
   
New York (NY) Daily News
CREMA’S REFINED MEXICAN RANGES FROM HOT TO HAUTE !
BY PASCALE LE DRAOULEC
Friday, June 16th 2006, 1:15AM
CREMA
111 W. 17th; (212) 691-4477; Visa, MasterCard, Amex 2.5 STARS.
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When describing huitlacoche - a corn fungus considered a delicacy by many - the server at Crema called it “a Mexican truffle.”
     
Village Voice (NY)
Feast of Fungus
A Huitlacoche outbreak in the East Village
Nina Lalli
Tuesday, August 22nd 2006
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The huitlacoche was earthy and mellow, but not the intense morel or shitake I was expecting. (In 1989, the James Beard Foundation held a fancy huitlacoche dinner and tried to rename the holy excrement “Mexican truffle,” but the euphemism didn’t catch on.)
   
Google Books
Mod Mex: Cooking Vibrant Fiesta Flavors at Home
By Scott Linquist, Joanna Pruess
Photographs by Shimon Rothstein, Tammar Rothstein
Published by Andrews McMeel Publishing
2007
Pg. 205 (Glossary):
Huitlacoche/cuilacoche: In Mexico, this corn fungus is a food delicacy to be savored. it is also called “Mexican truffle” or “Mexican caviar.’ The kernels have a smoky-sweet flavor.
 
Gogle Books
The Texas Hill Country Cookbook:
A Taste of Provence
By Scott Cohen and Marian Betancourt
Photographs by Ron Manville
Guilford, CT: Globe Pequot
2007
Pg. 31: 
The smoky, sweet flavor of this soup comes from the huitlacoche, a corn fungus that is also known as corn truffle and Mexican truffle. It would be difficult to get the native corn that is grown to create this delicacy, so we use the canned huitlacoche found in specialty and Mexican stores.
 
suite101.com
Huitlacoche: The Mexican Truffle
Don´t judge a mushroom by its looks!
© Sarah Menkedick
Mar 11, 2007
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Huitlacoche (pronounced wheat-la-coach-ay) is a black mushroom that grows on corn. Its gothic appearance (like a terrible moldy fungus devouring the innocent yellow corn) earned it the name “filth of the raven” in prehispanic Mexico.
 
With such a majestic title, who wouldn’t be intrigued? Huitlacoche has earned a reputation as a delicacy in Europe and the United States and can now be found in the most elite of Mexican restaurants (folded into ravioli, pureed into molé); happily, however, it has not lost its place as a staple of the Mexican diet, particularly in the indigenous communities of the South.