This is one of the three proper ratty taquerias (and I mean that in the best possible way) that we have here in Madison. A proper ratty taqueria isn't usually all that ratty, but does serve real Mexican food instead of Miswestixan at places like Laredo's or Pedros. No mass quantities of dairy and refried beams here.
My other chosen proper ratty taquerias in Madison are El Pastor and Taqueria Guadalajara. I'm a west-sider so have to drive a bit farther to get to those places, but I tend to go to Guanajatense because it's GOOD and closer to me. I usually just get a few tacos and swill back a couple Tecates in a can. They don't have tamales every day, but if they do they scribble "tamales hoy" on the specials chalkboard on your way in. Whatever else you're having, do yourself a favor and get a tamale too if they're available. The huaraches are MASSIVE and whatever the plate with the grilled cactus is called is also really good. They even use Black Earth Meats for the farm-to-table folks. I like spice so I dig the salsa bar but for those less tolerant of spicy food sometimes it's hard to figure out which one is mild since there aren't any labels. So yeah, go there and eat.