We all know that dumping shredded cheese on top of a taco is a purely gringo affair, right? That down in "real" Mexico, nobody would ever consider tainting their taco with the stuff? A few weeks back, when my wife, Adri, and I were in the Yucatán, we discovered that not only is this not true—tacos with cheese were found all over the place*—but, more importantly, I learned a completely new technique for incorporating cheese into tacos that takes it out of the realm of "Okay, that cheese is melty and, by default, delicious" and into "Holy crap, this cheese tastes like it was curdled from milk drawn from the teats of virgin bovine angels."
* If this is a new development, I say it's a welcome one!
We had it in some delicious pork belly tacos, but the technique works for any taco filling.
On our third day in the Yucatecan capital of Mérida, my wife and I took a long early-morning walk through the hot Spanish colonial streets to sidle up to the bar at Wayan'e, one of the city's busiest taco stands. There were over 20 different taco fillings on display in ceramic bowls the size of dinner plates, which busy cooks would refill as they emptied out. When I'm faced with a spread like that, I have trouble picking, so I have a couple of fallback ordering strategies, both of which we applied that morning.
The first is to not pick. Just start ordering and ordering, and stop only when the person taking your order starts to look incredulous about the amount you just ordered. That's how we wound up with two egg tacos (one with nopales—cactus pads—and one with chaya, a local green herb); a taco with chili-marinated pork shoulder; an empanada with cheese and squash blossoms; a duet of tacos filled with tender chicharrón (braised pork rind, with red sauce in one, green in the other); a taco with pork loin in a tomato sauce; and a taco topped with chorizo and chipotle-seasoned black beans that were seared in a patty on top of the comál, the hot steel griddle used to crisp fillings and soften tortillas.
Hungry from our walk, we wolfed them down with an avocado purée and dabs of chile tamulado, the fiery roasted-habanero salsa served at every table in town. Tall glasses of agua fresca de jamaica (hibiscus-flavored water), served out of empty votive candle jars, cooled down our mouths. (We checked: The ice there was safe, even for gringos like me.)
It wasn't until we'd cleared half our plates and started ordering a new round that we noticed the man sitting next to us. More specifically, we noticed what was in his hand. It looked cheesy and delicious, and we employed my second ordering technique by pointing at it and indicating to the cook, "I'll have what he's having."
Castacán is the Yucatecan version of crispy pork belly, which, according to local expert David Sterling's awesome book, Yucatán, would typically be a specialty of the chicarronerías, shops that take pork scraps and offal and slowly simmer them in vats of rendered pork fat until tender and crisp. When we ordered the tacos, the cook chopped up a small handful of meat on a wooden cutting board, then placed it on the hot cómal. As soon as the meat started to crisp up, he deposited a little pinch of shredded Oaxacan cheese directly on top of it.
As the cheese melted, it oozed into the cracks and spaces between the meat, binding the bits of pork belly together and browning where it came in contact with the pan. Eventually, the cook flipped the whole thing over to get direct cheese-on-cómal contact, letting it sizzle until the cheese browned and crisped, lending an extra dimension of nutty browned flavor and crisp texture to the finished taco. It was revelatory, and, as soon as I got home, I started working on a recipe for myself.
The real trick to making castacán at home is to forget the traditional method. I don't have vats of rendered pork lard lying around to simmer my pork belly in, and I'm guessing neither do you.
Instead, I use the technique I use for my carnitas recipe: I pack the meat into a container that just barely fits it, so that only a small amount of fat is needed to cook it. A two-pound slab of pork belly fits nicely into my 10-inch cast iron skillet—though, depending on the exact form factor of that slab, you should seek out any oven-safe container that it fits snugly into—leaving just enough space for about a cup of fat.
Rendered pork lard is good if you have it, but, since so much fat ends up rendering out of the pork belly as it cooks, I've found that even with canola oil, you still get plenty of porky flavor in the finished castacán.
It's not traditional, but I decided to add a couple of aromatics to the oil as well, just for another layer of flavor. Garlic, cloves, cinnamon, and orange are typical flavors of the region and work well. When it's covered and cooked in a moderate, 275°F oven, it takes about five hours for the connective tissue in the pork to break down and for the meat to fully tenderize.
Castacán is typically fried in the same fat until crisp, but I find that method a little messy—it tends to sputter and spit once you get it to a hot enough temperature. Instead, I finish it in the oven, placing the tender pork belly skin side up on a foil-lined rimmed baking sheet and roasting it at a relatively high 450°F until it's crisp and blistered on top. (I've found that I have to use the foil to shield the sides of the pork a bit to prevent it from burning.)
The finished pork should be tender and juicy inside, with a significant layer of crisp, crunchy crackling. To be honest, just chopping it up and stuffing it into a tortilla as is would be an amazing experience, but we all know what's happening next.
I chop up the meat and form it into little piles on my Mini Baking Steel Griddle (though a large cast iron pan or cast iron griddle will also work), letting them crisp up a bit while I warm some tortillas in the drippings.
I then add pinches of shredded Oaxaca cheese (low-moisture mozzarella works fine) to each little pile, letting the cheese melt and ooze through, just as I saw the cook do at Wayan'e. After a few moments of intense browning, I flip each pile over with a metal spatula to brown the second side.
Dios mío, are these tacos tasty. Crispy, porky, and well browned, with gooey pockets of melted cheese hidden throughout. All they need is the smallest dab of fiery chile tamulado** and maybe a little squeeze of lime to balance their flavor.
** El Yucateco makes a bottled version that is the closest to real I've tasted.
The only caveat: These things must be eaten fast if you want the optimal goo-to-crunch balance. Something tells me that's not going to be a problem.
Gooey cheese on real Mexican tacos. Next I'm going to find out that Taco Bell's Quesalupa is actually a traditional Oaxacan recipe. But I sure hope not, because Oaxaca is next on my list of "regions I must inhale."