Corn smut(Ustilago maydis), also known as Mexican truffles, corn truffles and raven scat is a fungus that grows on young maize. When the corn is in silk kernels become infected. They swell to golf-ball size galls and discolor. Loaded with soluble fiber, the amino acid lysine and the antioxidant anthocyanin, the moist young galls are collected two or three weeks after the corn becomes infected. If not harvested the galls will grow hard and spore-filled looking a smutty dark blue or black.
We eat these and put it on stuff in Mexico. It’s just like eating mushrooms or a mushroom sauce. I haven’t had it but a lot of people eat it and like it.