I apologize in advance, because this is a vague one.
20+ years ago, I ate several times at a Mexican restaurant that was north and west of downtown Chicago. The only things I can remember about it are:
1. borderline neighborhood, with el tracks overhead
2. the place had no liquor license, so customers were directed to a nearby liquor store to byob.
3. great food
4. very popular place...customers were lined up out onto the sidewalk waiting for tables
Anyone have an idea of the restaurant name and/or location I am trying to remember?