I've been following this thread since it's inception and it's getting weirder and weirder. I didn't want to jump in at the NYC, Chicago thing with "superior SoCal" knowledge, because it would have been offensive.
Look. There's no such thing as a single quintessential Mexican taco. And there's no such thing as the "best" taco stand in the US. And for all I know they make great tacos at Bannigans in Iowa City. For all you know, too.
Mexican cuisine is rich and varied. And when you talk about tacos -- even tacos in el Norte (that's the US of A and Canada for you gabachos), you've hit the motherlode.
A taco can be small, almost tiny. That's very common in taquerias with big selections, places where tacos are very cheap (those things go together); in D. F. (el Distrito Federal is Mexico City's real name) where they have big selections and cheap tacos, etc. A taco can be also be fairly large and overstuffed.
A taco, con todo, can be meat, onions, cilantro and a little salsa.
Some people might say you can't put beans in a taco, but who are they to say? Some people put lettuce and/or cabbage in theirs. Do you judge them? Some people get radishes, carrots, jalapenos either raw or en escabehe, and put them in the taco, others eat them along side. Who's right? What do you know about it?
Is a taco suave (taco in a soft tortilla) the only true taco? Tacos dorados (crispy tacos) simply don't count? Where is that written?
Of these, what's the true taco filling? And what doesn't meet (sorry, can't help myself) your standards.
Al pastor
Tripa
Machaca
Suadero
Mollejas
Buches
Asada
Ropa vieja
Lengua
Birria de chivo
Carnitas
Picadillo
Cabeza
Pollo
Cecina
To name a few
As of the 2000 census, there were more than 2,000,000 Mexican hispanics who live in Los Angeles County (not City). If you expand it to the megalopolis that L.A. really is (including Ventura, San Bernadino, Riverside, and Orange Counties) the number is something like 3,000,000. More if you add San Diego and Santa Barbara -- which you very easily could consider part of greater Los Angeles.
Greater Chicago had about a quarter of that. NYC has a lot of hispanics, more than 2 million, but so many are Caribbeans -- I think the number of Mexicans was actually a little lower than Chicago.
There is no best taco stand. How can you compare some place in Chicago with a place in "East Hollywood" that sets up at night in a body shop's parking lot? Especially when you've never been to East Hollywood, and even the location is unfamiliar? Who has the best buche?
There are thousands and thousands of taco stands here. There are hundreds of taco blogs for cry sakes! And by "stand," I don't just mean permanent building but carts, trucks, and the hundreds of "tables" that get set up in parking lots at night. How could anyone experience enough of them to seriously undertake the concept of "best?" And even then, how could you compare the lengua at one to the tripas at another? Plus, the quality of the taco served depends on a number of variables which vary from hour to hour. One place could be the best cabeza today, but only very good tomorrow. Of you could get a piece of gristle...
Al pastor alone... Do you only count it off the spit? Or is marinated and grilled good enough?
If El Chivito wants to eat flour tortilla tacos, that's his business. If that's how his family did it -- more power to them. My personal take on it is that flour is more Southwestern than Mexican, but who am I to say? It's not how people from the areas that feed the migration through Los Angles eat them. And you know what? If Chivito went to a taco stand and tried to order a taco in a flour tortilla in East LA, they'd just look at him -- sadly. But so what? That doesn't make him wrong. The tradition of Mexican cuisine holds his taco with as much pleasure as it does mine.
If Chris likes shredded cabbage on his, like the USC boys who go down to Ensenda -- more power to him. That may not be the way they eat them in Sinaloa, Jalisco and Michoacan, but so what? The way they eat them in Sinaloa, Jalisco and Michoacan isn't the way they eat them in Oaxaca either. Or in DF or Vera Cruz or around Guadalajara.
I mean really.
So what is a taco? The word means something cylindrical, like a bolt, a ladies shoe heel, a plug for a hole and doesn't have any culinary meaning at all in Spain. That implies that back in the 16th C., when the Dons stumbled on the tortilla, people rolled food up in them. They usually don't come rolled anymore. But if one did, would it still be a taco?
Now it's mostly some kind of food, folded into a tortilla.
At home it's frequently leftovers. Any leftovers. This expands the universe of tacos to the universe of whatever a Mexican will eat which is a pretty inclusive set of foods. You cup a tortilla in your hand, you put some food in it, you fold the tortilla, you eat the taco.
Some taquerias in DF have more than 20 choices of tacos. Probably not as good as the ones in Chicago though.
Here in SoCal, what you expect from a proper taco stand, truck, cart, or "table" is two corn tortillas, properly softened by being moistned with oil and heated on a piece of flat steel; a scoop of filling (lots of possibilities); onions, cilantro, a little fresh salsa on top; and a little bit of vegetable garnish and/or chiles to eat on the side. No cabbage, except for fish tacos. No lettuce. No tomatoes. No cheese. Not ever? Well, no. Because sometimes...
Sometimes there's one salsa, sometimes a choice. Almost always, unless there's at least three, none of them will be "fresh salsa" with chunks of fresh tomato. If there's only one, it will usually be reconstituted dried chiles, pureed in the soaking water.
And so it goes.
If you like the mystery meat, crispy tacos from Jack In The Box are the bomb, I'm not going to tell you no.
By the way, the chicken in a chicken taco is most often simply grilled (on a griddle or flat top) with salt and pepper -- then served with onions, cilantro and salsa. Unless you're at a pollo ala brasa place, then it's not ala parilla. If you know what I mean.
Experience the wonder that is the taco,
BDL