There aren't many places left in the world where you can stop on the street and snack on something made in almost the exact same way as it was 500 years ago. Mexico happens to be one of those places. While certain items have become so ubiquitous it seems Mexican cuisine couldn't exist without them – pork, garlic, lard, citrus fruit – the staples of the pre-Hispanic diet still remain a very real part of everyday eating south of the border. Let's dive back and get a pre-Hispanic food primer.
First, a look of what used to be Mexico's ancient diet. Bubbling not too far below Mexico City's asphalt jungle is an ancient system of lakes and rivers, atop which Aztecs developed one of the world's most efficient agricultural systems, the chinampas, floating fields that produced the empire's basic staples: corn, beans, chiles, and amaranth. For protein, ancient peoples turned to wild game and small mammals (armadillos, deer, buffalo, iguanas, ocellated turkeys, boars, and wild foul) before the Spanish brought pigs, cows, and chickens.
In the central region, indigenous peoples incorporated various cacti into their diet, while along the coasts, seafood, fish, amd salt were extremely important for survival and trade. And in the Valley of Mexico, lake fish, algae, freshwater shrimp, ducks, sand smelt (charales), and seasonal insects were all mainstays. Rounding out the diet were basic elements that can be traced back to almost every region (and still found today): corn, squash, chiles, tomatoes, and beans.