There is a Place in Paseo Colon, its on the street north to Pizza Hut.
Maria Bonita or something... Never been there but my brother tells me its quite decent.
Huaraches is great. I had lunch from Tacontento yesterday and it was awful. Not awful but expensive and you can get a better meal at Taco Bell.
La Botana Picante in La Rotonda de la Bandera used to be amazing (next to Fridays) however i believe last time I was around there it seemed closed.