Frank - you need to find a taquira kind of place there.
here's a list -
http://www.thecityofminneapolis.com/restaurant/#mexicanNot sure if the list is accurate.
Taco Cabana mixed taquira-style cooking with fast food prep techniques - and I agree with Terry - they did a bang up job up until about 2 years ago.
Tacos Morelos , Taqueria La Hacienda Taco , and Tortilleria La Peria look promising .. give it a shot, let me know the results ??
mondo regards [Bill]