Eating options in Banamichi are limited to a handful of small places, mostly tied to the town's accommodation. Don't arrive expecting a choice — but do expect honest Sonoran cooking.
The local staples are what you'd find across rural Sonora: carne asada, flour tortillas (Sonora is the home of the flour tortilla in Mexico), beans, and cheese from regional dairies. If you are here in autumn, the pomegranates and oranges from local orchards show up in juices and on tables.
Ask at your accommodation about meals — most small guesthouses in the valley will cook for guests given a little notice, and that is often the best food available.