Michael D. Coe and Stephen Houston report that maize was a common food staple in pre-Conquest Mesoamerica in both the lowlands and highlands.
Michael D. Coe and Stephen Houston, The Maya, 10th edition (London: Thames & Hudson, 2022), 12
While there are pronoun differences between the subsistence base of the lowlands and that of the highlands, the ancient foursome of maize, beans, chile peppers, and squash formed then, as it still does, the basis of the Mesoamerican diet. Cacao, a key flavoring, made life doubly pleasant. Of course these foods were found elsewhere, form the southwestern United States to Peru in pre-Conquest times. Some, such as maize, seem to have reached their full nutritional potential in South America after their initial domestication in Mexico. Cacao might have been first domesticated in that continent as well. In Mesoamerica, nonetheless, the preparation of maize is highly distinctive: the hard, ripe kernels are boiled in a mixture of water and white lime, producing a kind of hominy (nixtamal) that is then ground into unleavened dough on a quern (metate) with a handstone (mano), later to be fashioned into steamed tamales or into the flatbreads known by the Spanish term tortillas, “little cakes.” The latter, perhaps introduced into the Maya area in late pre-Conquest times from Mexico, are characteristically toasted on a clay griddle (comal) that rests on a three-stone hearth.