Experience (and in some cases, my experience is named Rene G) confirms cachete is cow cheek in Chicago, so you should be able to get it most places advertising "cabeza al vapor," steamed cow head tacos. I've just started to explore Taqueria Los Altos de Jalisco, both right across the street from the Depot (I provided 5827 W. Roosevelt earlier this year, can't get independent confirmation at the moment) and at 1922 Cicero, both in Cicero, and think they do a great job.
Buche, another word used for cheek in some textbooks and communities (compare with
bouche and
boca, mouth), won't net you a cow cheek taco in Chicago - if you see that you're rolling the dice (usually based on regional origin of the proprietors, sometimes on vocabulary of the resettled and mixed diaspora here) between (pig) esophagus, tripe, and regular old carnitas. It's a problematic word that can mean maw, mouth, cheek, neck, esophagus, belly, stomach lining, or anything fat or cute like the whole pig by synecdoche, and as a food term seems confined here to the realms of the porcine.