As far as I'm concerned, Atotonilco serves only al pastor. When it's on, it's one of the best versions around—crispy, caramelized, and charged with chiles.
'atotonilco' on Serious Eats
Are there actual differences between the many brands of corn tortillas in Chicago? Unlike many other foodstuffs, they don't travel well, and for the most part they need to be eaten on the same day they are made or else they turn brittle and dry. Luckily, Chicago is apparently awesome at making tortillas, at least according to Rick Bayless.