I started a similar thread a year or so ago but thought this was worth revisiting (because it is indeed a never ending quest!).
A few years ago dh & I made it a practice of trying all the local mexican restaurants. Our favorite is (and has been for quite a while) Rincon in Eastgate (near the Biggs). Really good chili verde, tamales, chili colorado, mole and enchiladas.
It seems new mexican restaurants are springing up in Cincinnati every day and it is hard to know which to try. I live north of the city (between montgomery & mason) and we haven't really found anything around us we like (we are giving El Toro a try tonight). Didn't care for Fiesta Bravo at all.
So whaddya think? Found any really good mexican food in Cincinnati?