The irony of corn smut is almost as delicious as the flavor. It's a multi-billion-dollar agricultural pest that's more valuable than the crop it destroys. But if you're a factory farmer with an infected cornfield and no infrastructure, market or stomach for moldy, grossly disfigured corn plants, you might as well plow the whole field under. And they do.
Corn smut has many names, one of which means raven shit in Nahuatl, the language of the Aztecs. Some call it Mexican truffle or Aztec caviar, but it goes most often by huitlacoche (hweet-la-coach-ay). Fresh, it can taste like the blend of mushroom and corn that it is. When the specimen is old, or from a can, it blackens like squid ink and thickens like flour and has a dark fungal earthiness with a hint of the sea.
Corn smut grows where corn plants are damaged, such as by insects or hail. Spores of the fungus Ustilago maydis find their way in to the developing corn kernels, where they grow into a fungal mass called mycelium. When it's time for the mycelium to flower and make smut babies, the kernels swell with millions of immature spores. Each kernel can grow as big as a golf ball, and together several neighboring kernels will form a tumor-like cluster that swells and bursts through the corn husks.
At first sight of the ol' porn on the cob, most people probably don't think, "Yum, a delicacy." More likely it's "Ew, nasty!" It looks like something that clearly needs to be thrown away.
Of course, that's a common first reaction to blue cheese, kimchi and select other specialty items that look absolutely disgusting but are actually incredibly delicious. While blue cheese is a combination of processed milk and fungus, corn smut is a blend of fungus and plant. In prime specimens of corn smut, in which the kernels are young, firm and intact, you can clearly taste both elements. The texture is firm, a little stringy and moist, like a spinach quiche that hasn't quite cooled.
Mycologist Larry Evans describes the taste as "olives and oysters." Evans, who's managed to put most every culinary mushroom on earth in his mouth, says corn smut is one of his favorites. He has favorite places in Mexico in which to eat it.
Much of the fresh corn smut consumed in the states comes from Mexico and goes primarily to restaurants. Finding it fresh retail is difficult. And eating it from a can is barely worth it. But if you live in a region where corn is grown, there's probably smut closer than you think.
Some friends and I grew a big patch of blue corn on a plot of borrowed land this year, and sure enough we found about ten infected ears. Somehow, I was nominated to eat smut.
I've had it before, and I know that its nutty, deep flavors are pleasing to me. But facing the fungus in raw form, I wasn't sure how to proceed. I called Evans and left a message. Then I called my local hamburger joint, which serves a great huitlacoche burger, and asked for advice.
"Just cook it however, man," said the guy who answered the phone.
"But," I said, "I mean, it looks a little nasty."
"Cut off the gross parts, cut it up and sauté it like a mushroom."
"But," I asked, "is there other stuff that looks like corn smut that actually isn't and can poison you?"
"No, bro. If it looks like smut that's what it is. It's everywhere. I got some at the Fruit Basket on 4th Street the other day."
"They sell corn smut at the Fruit Basket?"
"No. I was buying corn and I saw some on an ear. I was like, 'Sweet!' I brought it home and sautéed it with onions, garlic and green chile, bro. It was good."
This gave me the confidence to begin playing with my smut. After carefully removing six infected silver grey kernels from a cob and separating them, I put them in a skillet with olive oil on low heat. I placed thin slices of venison in the skillet among those scallop-like sacks of proto-mold spore. I stirred, making sure the meat and mushroom cooked on all sides, and then added chopped onions and garlic, followed a few minutes later with chopped tomatoes and, finally, chopped chili peppers. I used roasted green chilies, but chipotle or red chili would also work—anything with a soft, back-of-the-tongue fire. I ate it like stew, but it would be great in tortillas, too.
As I happily digested my meal, Larry Evans returned my phone call. His was the first opinion I'd sought regarding smut safety. He told me that smut fungus has killed more people than any other mushroom.
In addition to corn, close relatives grow on wheat, oats and other grains. In the early 1900s, a plague of exploding thrashing machinery took a huge number of farmers. The explosions were fueled by smut dust, which is highly combustible when dry. The dust is thought to have been ignited by static electricity in the cylinders of the thrashing machines, after being inhaled by the carburetors. During the summer of 1914 alone, 300 grain-thrashing machines exploded or burned in the Pacific Northwest.
"They'd hit a patch," Evans says, "knock up a cloud of dust, come back around and boom!"
And now there's a corn smut boom of a different sort, as foodies are smitten with smut the way they once fell for heirloom tomatoes.
Tracey Vowell used to be managing chef at the Rick Bayless restaurant Topolobampo, in Chicago, where she smutted everything from tortes to enchiladas. She left to begin a decades-long quest to grow the stuff. Nowadays, she inoculates her corn via syringe and produces more than a 1,000 pounds of corn smut a year, supplying, among other places, her former restaurant.
While Vowell's making good money selling smut at many times the value of the corn that's hosting it, her Midwestern neighbors continue to destroy fields of that same delicious and bizarre cash crop. That's a shame. Of all the uses for corn, including animal feed, corn syrup and car fuel, I think I love corn smut the most.