The Los Tios restaurants in Houston are some of the oldest, along with Molina's, El Patio and Spanish Village. Historically significant to the max and great Tex-Mex.
When I was growing up in Houston, the style of crunchy and puffy tacos was fairly common. Our family ate at a Mexican restaurant on Telephone Road at least twice a week that featured them (El Patio for those who grew up in the East End...there were several unrelated El Patio's around town at the time, one in River Oaks Shopping Center; the one still in existence on Westheimer; and others).
With the closing of Fiesta Loma Linda on Telephone Road, Los Tios is the only restaurant that I know of that carries on the tradition of the Houston style puffy taco and queso and also, the pecan praline candy that came with your bill at the end of the meal.
A lunch special here of a taco, guacamole, rice and beans will cost you less than a burger, fries and shake at Shake Shack. Here's the lunch special (actually you can pick two items from a list, but, I'll always go for the taco)
The manager of the Beechnut location confirmed to me what I already knew, having tried to make the puffy taco in my home kitchen. It is HARD. It is an art. And something that requires a skill that comes with time to perfect, in the hands of some ladies who have been with the Adair family restaurants for many years. The manager told me how, although new items have been added to the original menu, the classic "Number 6" is still the most requested and most popular!