The Food Lab: Great Chile Verde Without Hatch Chiles
We all know chili: thick, rich, spicy, meaty, complex, and red, right? But what about green chili, that equally complex, fresher, porkier cousin common to many Southwestern states?
I know that certain types of people are as uppity about their chile verde as Texans are about their... well, their chili. And here's the deal: no-beans is to chili in Texas as the Hatch pepper is to chile verde in New Mexico. That is, if it's got beans in it, it ain't chili in Texas, and if it don't have Hatch chilies, it ain't chile verde in New Mexico.
The most basic and hardcore version of New Mexico chile verde is made by simmering rich cuts of pork in a thick stew of roasted Hatch chilies, onions, garlic, salt, and little else. Braised until tender, the chili broth picks up the flavor of the melted pork fat while the uniquely sweet and bitter flavor of the chilies, made smoky from roasting until nearly blackened.
Grown in the town of Hatch (population ~2,000), in southern New Mexico, they provide a complex backbone that few other single-ingredients could ever do.
I don't spend much time in New Mexico. I have a thing about heat and dream catchers, and fresh Hatch chilies rarely make their way to the northeast, which leaves me with canned or frozen chilies. Neither of these two options roast particularly well, and that smoky char is the best part of green chile.
Luckily, I also don't place much credence in authenticity. I'll settle for delicious.
When making my own red chili, I more often than not take full advantage of the Northeast's liberal attitude towards legumes (and I defy any Texan to taste my bean-filled chili and tell me it's not delicious). So when developing my own chile verde recipe, I decided that I'd take an equally liberal attitude towards my Hatch peppers. I live far enough away from New Mexico that hopefully I'll be able to see the dust trail roused up by the violently inclined green chili fanatics approaching and beat a hasty retreat.
It's certainly possible to get some form of Hatch chile to your door, no matter where you live. The internet is rife with Hatch chile distributors, promising to ship you authentic canned or frozen peppers straight from the source.
The problem with these is not really a texture or flavor problem—it's just that canned or previously frozen chilies are downright impossible to char properly before stewing them. They're simply too wet. Pre-roasted canned or frozen chilies don't have the deep flavor of home-roasted chilies, which left me with one option: find some suitable substitutes.
Poblano peppers were an obvious place to start. They're readily available, and have a deep, earthy flavor. To add a bit of brightness and some of those characteristic bitter notes to the mix, I also added a few sweet cubanelle peppers. A small amount of Jalapeño, with their heat and grassiness rounded things out.
If you want to go for full-on smoke, you can light a fire in an outdoor grill and roast your chilies directly over the glowing embers until completely blackened all over. For us apartment dwellers, roasting them over an open gas flame works just as well.
The goal here is total carbonization of the exterior. As it heats, the liquid just under the surface converts to steam, forcing the skin outwards and away from the flesh. This small area of air and water vapor just under the skin insulates the flesh underneath, preventing it from burning.
After the pepper is completely blackened, the loosened peel slips right off under running water, leaving the flesh clean and un-charred, but infused with deep smoky flavor from the blackened skin.
Even amongst the not-too-zealous chiliheads out there, tomatillos are a point of contention. A member of the tomato family (though it's completely different from unripe green tomatoes), it's actually most closely related to gooseberries and Chinese lanterns.
See how similar they are? Their flavors—dominated by a citrus-like tartness with a distinct, savory finish—are remarkably similar as well, though gooseberries tend to be sweeter. The great thing about tomatillos is that they are also quite high in pectin, a sugar-based gelling agent that is the primary thickener in most jellies.
The classic British whipped cream and fruit fool was originally made with gooseberries. The large amount of pectin would set the whipped cream into an almost panna cotta-like gel as it cooled, giving it texture and structure.
What this means is that by including tomatillos, you don't really need any other thickener in your chili (many classic tomatillo-less recipes call for flour or other starches), and the tartness it brings to the party is a welcome flavor addition as well.
Unlike chilies, tomatillos shed a ton of liquid when you try and roast them, so I found that cooking them under a preheated broiler was the best method to add some char without losing too much juice.
I know you might be thinking so far: is this a Food Lab post? Where're the little hacks and tricks?
I blame it on the snow. There's something about frost-covered windows that makes taking comfort in classic techniques all the more enjoyable.
It's times like these when the importance of every detail really comes out—charring every surface of the chilies to maximize smokiness. Carefully monitoring your roasting tomatillos so that they char and soften while still retaining some of their fresh acidity. Sometimes, the process of slowly, deliberately building flavors is just as rewarding as the finished dish.
Well look at me, I'm rambling again. Anyhow, pork.
Red chili is all about beef, but with green chili, pork is kind. I tried a few different cuts including sirloin, belly, country-style ribs, and shoulder. The shoulder and sirloin fared the best, maintaining moisture and favor throughout their cooking. The belly was simply too fatty, and while parts of the ribs were great, other sections cut nearer to the lean loin of the pig were much too dry for a stew. Pork shoulder requires a bit more work to get ready for stewing (boning, trimming away excess fat), but it's significantly cheaper, which gives it an edge in my book.
In my previous chili experiment, I found that browning small pieces of meat is a very inefficient method, and that it's much better to brown whole cuts, and chop them up afterward. With shoulder, that's a little more difficult—you basically have to dismantle the whole thing to clean and bone it properly.
My solution? Rather than browning all of the pork, I only brown half of it, allowing the pan to develop a rich, deep brown fond before adding onions and the rest of the pork. The coloring built up by the first batch of pork is more than adequate to give the finished dish rich, meaty flavor. On top of that, the tender texture of un-browned pork is far superior to that of the browned stuff.
The only question remaining was how to cook the dish. Oftentimes, for short-simmered sauces, I'll do 'em directly on the stove top, just keeping an eye on them as they cook to prevent them from burning. However, for braised dishes that need to be cooked for upwards of 3 or 4 hours, the stovetop shows a couple of distinct disadvantages.
The most obvious is that on the stovetop, the stew cooks only from the bottom, which can lead to food burning onto the bottom of the pot if you aren't careful. An oven mitigate this by heating from all sides at the same time. Moreover, a gas or electric flame set at a certain heat level is a constant energy output system, meaning that at any given time, it is adding energy to the pot above it at a set rate.
What this means is that at the beginning of cooking, when you've got whole lot of chili in the pot, your burner may only bring the pot to a bare simmer (the right temperature for braising). But as the liquid in the pot slowly evaporates off, its volume gets smaller and smaller. Since the burner is still putting the same amount of energy into a smaller amount of stew, your bare simmer might become a rolling boil halfway through cooking.
An oven, on the other hand, is a constant temperature system. That is, it's got a thermostat that controls the temperature of the air inside, adding energy as needed in order to keep the temperature in the same basic range. That means whether you are cooking a giant pot of stew or the Derek Zoolander Stew for Ants, it'll cook at the same rate from beginning to end.
For these reasons, it's better to cook in the oven for long, thick braises. But here's another question: lid on, or lid off?
If you believe classical wisdom, you want your lid on there as tightly as possible, in order to maintain moisture. It makes sense. More moisture in the pot means more moisture in the meat, right? Unfortunately, that's not really how braising works.
Basically, when you are braising, there are two counteracting forces that you need to balance.
- Collagen breakdown—the conversion of tough connective tissue into soft gelatin—begins slowly around 140°F and increases at an exponential rate as the temperature goes up. Pork shoulder cooked at 140°F may take 2 days to fully soften, while at 180°F, the time is cut down to a few hours.
- Muscle fibers tigthen and squeeze out moisture as they are heated. This begins around 130°F, and gets worse and worse as the temperature rises. Unlike collagen breakdown, which takes both time and heat to take place, with muscles squeezing, it happens almost instantaneously—meat that has been heated to 180°F, even for one second will be dry.
Like an unstoppable force meeting an immovable object, it's nearly impossible to achieve collagen breakdown without simultaneously squeezing muscle fibers. The good news: the gelatin created by collagen breakdown goes a long way to mitigating the drying effects of tightening muscle fibers, but the real key to a well-cooked braise is to cook it at a moderate enough temperature that the meat doesn't enter the so-tight-even-gelatin-can't-save-it range.
Now we all know that water boils at 212°F, right? But interestingly enough, even in a 250°F oven, you can greatly affect the temperature of the water inside of a pot by allowing or disallowing evaporation. This is because evaporation, the act of converting water into steam takes so much energy—it takes more than five times as much energy to convert one gram of water into steam as it does to raise that same gram of water's temperature by one degree!
Check out this graph demonstrating the braising temperature of a pot with the lid sealed versus that with the lid left slightly ajar:
With the lid closed, the liquid inside the pot floats at around the boiling temperature, sometimes even dipping above it (the pressure from the heavy lid allows the liquid to go above its regular boiling point, just like in a pressure cooker). Meat ends up overcooking, and by the time its tender, it's also relatively dry and stringy.
The uncovered pot, on the other hand, stays a good 20°F lower, keeping the meat inside at a temperature far closer to the ideal. Meat gets tender and retains moisture as it cooks, giving us a far juicier, more tender end result.
Don't you just hate that? You try your hardest to be cool and just write about the joys of slow-cooking pork, then a graph has to go and sneak its way into the works. Graphs are always doing that to me. My apologies. It is the Food Lab, after all.
Anyhow, at least now you understand exactly why your pork chile verde is so deeply flavored, succulent, and complex, and maybe also why my conversation topics don't get me invited back to too many parties (except potlucks, oddly).