Quesadilla de Huitlacoche

Huitlacoche is a pre-Hispanic Mesoamerican ingredient: the swollen blue-black galls that form when the fungus Ustilago maydis (corn smut) infects the ears of maize, prized as a delicacy in central Mexico rather than discarded as a crop disease. It has been eaten since at least Aztec times, and the name itself is Nahuatl, though its precise derivation is debated — it is usually parsed from cuitlatl (an outgrowth or excrescence, sometimes loosely glossed as "excrement") plus a root meaning "to sleep," giving a reading often rendered as "sleeping excrescence," said to describe how the fungus grows over the kernels and leaves them dormant. In the United States it was rebranded the "Mexican truffle" after a 1989 dinner at the James Beard House in New York. Quesadillas are a colonial-era development built on the pre-Hispanic masa tortilla, and huitlacoche became one of their classic fillings; a precise "first quesadilla de huitlacoche" cannot be reliably dated.

The filling is earthy and mushroomy, savory and faintly sweet, with a soft inky-black paste that stains the masa. There is real smoke and char from the comal, the toasted-corn aroma of the masa itself, and a resinous, almost medicinal herbal lift from the epazote that is essential here, not optional. The chile adds a clean green heat. If made with cheese, the quesillo pulls into long molten strands; the purist cheeseless version lets the huitlacoche stand alone. A squeeze of lime cuts the richness.

The masa is nixtamalized corn: the kernels are steeped and cooked in an alkaline lime (calcium hydroxide) solution at roughly pH 11–12, which dissolves the hemicellulose gluing the cell walls, loosens the hulls, frees bound niacin and makes the corn's tryptophan available (preventing pellagra), and adds calcium. Crucially it lets the ground corn form a cohesive, plastic dough even though corn has no gluten — without nixtamalization, plain cornmeal will not bind into a tortilla. The huitlacoche itself is the fungus Ustilago maydis, which on infecting the ear converts kernels into swollen galls rich in glucose and other simple sugars and higher in protein and lysine than healthy corn; cooking concentrates those sugars and drives Maillard browning, deepening the umami and turning the galls blue-black. On a comal held near 200°C the raw masa sets and chars via the Maillard reaction, and because the tortilla is folded around the filling and cooked from raw, the masa and huitlacoche fuse into one piece rather than sitting as separate layers.