I spend a disproportionately large amount of time pondering the seemingly improbable origins of some of the world's most important foods. What were the chances, for instance, that anyone ever managed to figure out that soybeans could be dried, boiled, puréed, strained into a milk, and then coagulated with sea salts to make tofu? Or that grains and fruit could be left to basically rot, then boiled in a closed system designed to trap invisible alcohol vapor, condensed in a cooling tube, and the liquid harvested for use as an extra-strong intoxicant?
Perhaps the one that fills me with the most awe is the discovery of the nixtamalization of corn by Meso-Americans thousands of years ago. The process involves cooking and soaking dried corn kernels with calcium hydroxide (slaked lime) or another alkali, which removes much of the grain's bran, significantly increases the availability of niacin in the corn, and delivers other nutritional benefits. How they ever figured out that they needed to cook the corn with cal, as lime is called in Spanish, is beyond me, given that they didn't know anything about niacin, the consequences of not eating enough of it, or how their staple grain, corn, was involved. It's a good thing they did, though, because their health hinged on it.
It was also a good thing gastronomically, because nixtamalization changes the flavor of corn in amazing ways, and, by removing the bran, makes it much easier to grind and form the corn into a dough—especially in ancient times, when this was all done by hand. The result: a corn dough, called masa in Spanish, that's responsible for much of the Mexican food we love today, from tacos to tamales, quesadillas to sopes, and gorditas to atoles.
Tacos, of course, require tortillas, but, more importantly, good tacos require good tortillas. We can take that a step further and conclude that great tacos need great tortillas. This simple fact haunts me daily, since I live in a neighborhood with a huge Mexican population and not a single good tortilla...which means not a single good taco.
Well, not anymore, because good tortillas are now within my reach. And soon they'll be within yours, too.
Is It Worth the Trouble to Make Tortillas From Scratch at Home?
I'm not entirely sure why the Mexican restaurants and food trucks in Jackson Heights, Queens, where I live, lack good tortillas, but my best guess is that the businesses don't exist to provide that kind of large-scale fresh masa and tortilla production. Most food vendors just make do with shelf-stable packaged tortillas instead. It's possible that at home some people make more effort, using either masa harina (dehydrated nixtamalized corn flour) or, maybe in more limited cases, their own freshly nixtamalized corn. Masa harina, it's worth noting, is the easiest way to instantly improve your tortilla quality at home—pick up a bag of it at most well-stocked groceries (Maseca is a common brand), add water, and you're good to go.
The question, then, is: If low-quality packaged corn tortillas are good enough for all these Mexican businesses and their customers in Jackson Heights, and if home cooks are mostly turning to masa harina when they prepare fresh tortillas, is it really worth trying to make fresh nixtamal from scratch at home?
It's a difficult question, but my answer, in a nutshell, is almost always yes—at least, for most of us. If you're lucky enough to live in a place where good tortillas are readily available, then I suppose it may not make sense to put in the extra effort to make your own, although even then I might argue that going through the nixtamalization process yourself is incredibly edifying. It's the best way to see just how transformative nixtamalization is.
If you don't live near a source of good tortillas, then the answer is absolutely yes. The best news of all is that, once you've gotten hold of the key ingredients, it's also ridiculously easy.
Arriving at a Method That Works
If this sounds like a daunting undertaking to you, don't worry—you're not alone. I've had from-scratch tortillas on my to-do list for more than a year, the 25-pound bag of dried corn that I ordered back in December of 2014 a constant reminder of a recipe and article I just couldn't seem to work up the courage to tackle. The funny part is, once I finally got to work on it, it took me no time at all. What the hell had I been waiting for? Which is all to say, don't be like me and allow an imagined difficulty to put time between you and amazing tortillas at home.
Part of what made this project easy was a couple of existing resources that helped set me on the right path immediately. First, there's Dave Arnold's incredibly detailed and thorough article on his own nixtamal testing, which is absolutely worth a read. (Arnold went so far as to try grinding the corn by hand on a traditional metate a mano, an endeavor I didn't even consider.) And then there's my friend Jordana Rothman and the chef Alex Stupak's book, Tacos: Recipes and Provocations, a must-read meditation on all aspects of the beloved food, including nixtamal.
The single hardest thing about making fresh tortillas at home is getting the two main ingredients: dried corn and lime. And even that isn't too hard. For the corn, you want to track down dried dent or field corn, which is starchy, not sweet. (Sweet corn and popping corn will not work.) There are more varieties of this kind of corn than I can keep track of and test, but, from everything I've read, just about any of it should be good, whether it's white, yellow, or blue. The 25-pound bag of yellow corn I bought from Great River Organic Milling through Amazon worked perfectly. Yes, I know that's a lot of corn, but, on the other hand, it doesn't seem to go bad—like I said, I've had mine since 2014.
Dave Arnold writes in his article that he bought his corn through Rovey Seed Co., so that might be worth checking out. You can also try to find smaller quantities at a good Mexican market, or possibly from a farmers market, if someone there sells dried field or dent corn. It also looks like Anson Mills has yellow corn that should do the trick.
For the slaked lime, I think your best bet is to grab a bag of pickling lime, which is widely available online and at some retailers. You could also try to find cal at Mexican markets, which is essentially the same stuff. Whatever you get, just make sure it's food-grade slaked lime and not lime for nonedible industrial applications.
You'll also need a tortilla press—ideally a heavy cast iron one and not a lightweight aluminum one, for ease of pressing—and a food processor. Oh, and go grab a bag of masa harina para tortillas as well. It'll come in handy.
What you won't need is a grinder like the one in the photo below. It's a clunky piece of gear that's not worth investing in if you don't already have one. I tested one out, and, while it works, according to Rothman and Stupak in Tacos, these grinders can sometimes produce masa that's too coarse for tortillas, even after multiple grindings.
If you already have a grinder like this, feel free to try it out; you may be able to get it to work. Otherwise, the food processor is your best bet at home.
Homemade Tortillas: Step by Step
Simmer, Steep, Then Wash
The day before you want to make your tortillas, combine the dried corn with water and cal in a nonreactive (i.e., stainless steel or enameled) pot. I've been using a ratio of 1.5:100:300 by weight for the lime, corn, and water, so, for 1,000 grams of corn (1 kilogram), I add 15 grams of the lime and 3 kilos of water, and it's worked well.
Doing this all by weight is, I think, the surest way to go, especially for the lime, which can have different densities depending on the form it comes in (sometimes it's powdered, sometimes caked). Because the lime is weighed in such small quantities, you'll also want to make sure you have a kitchen scale that's sensitive enough to register it. Absolute laser precision isn't essential, so even our recommended OXO kitchen scale, which is only sensitive to the gram, is okay, although a more precise scale that can register tenths of grams (or hundredths) will give you a more exact result.
Bring the water to a simmer, and cook it until the corn has lost its raw edge but still has a tiny starchy core—you can tell by pulling apart a kernel and looking inside, as in the photo below. The key is that the starchy corn be mostly hydrated and tenderized, but not so soft as to be totally cooked through. Exactly how long this will take is impossible to say, since different varieties of corn will take different amounts of time, but to give you an idea, mine took about 45 minutes. You want the corn to remain submerged, so top it up with more water if needed.
When the corn is ready, cover the pot and let it steep at room temperature overnight. The next day, the bran on the corn should slip off easily.
Dump the corn into a colander and rub it between your hands while running cold water over it. The idea is to remove much of (though not necessarily all) the bran. The corn should quickly take on a lighter shade as the bran comes off.
Now transfer your nixtamalized corn to a food processor and turn it on. Add cold water, little by little, to loosen the mixture and help the blades process the corn. Scrape down the sides of the processor bowl, and keep going until you have a purée that's the consistency of hummus, with no big corn chunks. This can take about 10 minutes, and you will likely have to add a fair amount of water to get there, though just how long it'll take and how much water you'll need will depend on your corn and your processor.
At this point, you have masa, but it's too wet to make tortillas. Scrape it out into a mixing bowl.
Here's where that bag of masa harina comes in: You're going to add just enough to absorb the extra water and bring the consistency of the masa back to where it should be, which is about the texture of Play-Doh. Sure, it's a small cheat to work a convenience product like masa harina into the otherwise from-scratch dough, but it produces excellent results, with a pure, fresh nixtamal flavor—all without requiring specialized equipment.
One good test I learned from Rothman and Stupak's book is to squeeze a small ball of the masa: If the edges crack as you squeeze, it's too dry. If that's the case (meaning you used too much masa harina), add more water, or you can add more masa harina if it's too wet.
Form Tortillas and Cook
With the masa just where you want it, it's time to press and cook the tortillas.
Start by cutting two sides plus the zipper-top off a large zipper-lock bag so that only one side is attached. You'll use this to line your tortilla press and prevent the masa from sticking to the metal.
Then roll the masa into balls about the size of golf balls, and flatten each one slightly. One at a time, set the portioned masa between the sheets of plastic and press it flat. There's some art to getting the pressing right. If you press too hard, the edges of your tortillas will be too thin. Don't press hard enough, and they'll be too thick. Aim for somewhere around a millimeter in thickness, or just a little thinner. Tortilla presses don't often press the tortilla evenly, so I find that it's best to press once, then turn the plastic 180 degrees and press again to even the circle out.
Carefully peel the masa round from the plastic and place it on a preheated griddle or cast iron pan. You want the surface hot but not blistering, and seasoned but not wet with oil. If the cooking surface starts to dry out during the cooking process and causes the masa to stick, just rub the griddle or skillet with a paper towel that's lightly moistened with oil, making sure to buff out any wet sheen.
The tortilla will usually puff up and even brown in spots as it cooks. That's all fine; just turn it with a thin spatula to cook both sides. You can also flip it repeatedly until it's done. Done, in this case, means that the surfaces are dry, maybe lightly browned, but the center still has some moisture and elasticity. What you don't want are tortillas that have dried into crackers: They should be pliable and foldable.
Transfer them as they're done to a towel or tortilla holder that you can keep wrapped around them to trap steam and heat. Cold, dry tortillas are the worst, so you want to delay that eventuality as long as possible.
With a couple of skillets or a large enough griddle, you can get a rhythm going and pump out quite a few tortillas in a short time. I promise, once you get your hands on the ingredients and do it one time, there'll be no going back.