I think it is Pinole ( https://en.wikipedia.org/wiki/Pinole ). It is a very tasty powder we have here in Mexico that we use to do some type of milkshakes. I loved it as a kid.
From the cultivated crops the Tarahumaras prepare the following foods: Pinole, finely ground corn meal, is the
most common. The meal is mixed with water and the mixture
is drunk. A trait shared by many tribes of northern Mexico and the American Southwest, pinole is an ideal preparation for the highly mobile Tarahumara who carries, in a pouch slung under his arm, enough pinole to last him as much as a week while he is on the trail. Esquiate is similar to pinole but is prepared slightly differently, and, not being a dry meal like pinole, is not as transportable. It too is mixed with water and drunk. It is consumed as commonly as pinole and with this latter constitutes probably 75% of the Tarahumara?s diet. Other corn preparations, used less frequently, are atole (gruel), roasting ears, tortillas, tamales, and the cornflower.
Source:
Champion, J. R. (1970) ‘Study In Culture Persistence: The Tarahumaras Of Northwestern Mexico’. Ann Arbor, Michigan: University Microfilms. Available at: https://ehrafworldcultures.yale.edu/document?id=nu33-013 (Accessed: 22 August 2019).
Source:
Champion, J. R. (1970) ‘Study In Culture Persistence: The Tarahumaras Of Northwestern Mexico’. Ann Arbor, Michigan: University Microfilms. Available at: https://ehrafworldcultures.yale.edu/document?id=nu33-013 (Accessed: 22 August 2019).