I too went to Nuevo Leon, actually sometime ago, and was dissapointed by the looks of the place, floors etc.
and my chorizo breakfast was somewhat dried up. I felt perhaps it was not what it was anymore. However now there actually a lot of choices for Mexican breakfast in Chicago.
One of my favorite though is in Waterford, Wisconsin, Marty's, a small town diner, actually the diner is now pretty big, owned by Mexicans. They serve both American and Mexican fare. Their Mexican breakfast and
lunches are quite good and it makes an interesting study to see local folk dining at a restaurant owned by Mexicans and how in smalltown USA such integration succeeds, especially when good food is served.