The other day, I was tweeting about the relative popularity of mayo versus butter as a sandwich spread, when my pal Harold Dieterle made the observation that Vietnamese banh mi sandwiches are more popular in the US than they are in Vietnam. I think he's probably right. It's one of the handful of dishes that have come to represent Vietnamese cuisine on English-language menus. And, if banh mi are the hand-eaten snack, and pho is the spoon-fed hangover cure, then thit heo nuong xa—grilled pork chops with a sweet-and-savory marinade—are the knife-and-fork main course.
Thit heo nuong xa also turn out to be the easiest dish to replicate at home. You don't need the special bread required for a good banh mi; the most difficult-to-find specialty ingredient is fresh lemongrass, which is even available at most national chain supermarkets these days. You don't need to spend hours constructing a delicately aromatic broth, like with pho; this is a dish that takes maybe half an hour of active work, at most. All you need is a few common ingredients for the marinade—shallots, lemongrass, garlic, sugar, pepper, and fish sauce—and some thinly sliced pork chops, plus a nice, hot fire and a couple of mandatory sides: steamed rice, sliced cucumber, and a simple sauce to accompany them all.
Oh, and one more thing: a mortar and pestle.
I hope I don't sound like a broken record when I say this, but if you don't own a good, heavy mortar and pestle, it's time you took action to fix that. These pork chops should be as compelling a reason as any. I know that there are those types of people who insist on using specific tools for cooking the foods of a particular region of the world. I'm not one of those people,* which means that when I recommend getting yourself a mortar and pestle, it's because it's truly one of the most valuable and useful kitchen tools you'll ever own.
Okay, I am one of those people, but I insist on it only for myself.
Whether it's smashing small quantities of spices (much more efficiently than an electric spice grinder), extracting flavor from herbs for marinades or sauces, or helping to form emulsions between vegetables and oil, a mortar and pestle will surprise you with its versatility and usefulness.
For a marinade like this one, which is based on extracting flavor from moist aromatics, it's an almost indispensable tool. As you grind down lemongrass, shallots, and garlic on the rough stone surface of the mortar, cells get crushed, releasing aromatic juices from inside. It's a very different action from the slicing that happens in a food processor. Think about the difference between stepping on a bunch of grapes and cutting them very finely with a knife. Crushing delivers more juice, and hence more flavor.
It helps to add salt and palm sugar directly to the mortar at the start of crushing. Both of those crystals act as abrasives, making the crushing action much easier. That said, if you find it a chore, here's a compromise: Start your marinade with the mortar and pestle in order to get the lion's share of the crushing done, then finish by transferring it to the food processor for a smoother texture. For this particular recipe, total smoothness isn't even a requirement. I kind of like the crispy bits of charred lemongrass fragments that remain from a roughly smashed marinade.
Once the aromatics, salt, and sugar are reduced to a paste, I add fish sauce and a little oil and whisk it all together in a bowl before adding the pork chops.
The real magic of this dish lies in the pork chops' ratio of surface area to volume. This isn't a situation where we're looking for juicy, medium-rare, thick-cut chops. We want pork chops that are thin, about a quarter inch or so, so that we get maximum browning and crisping.
Because our chops are so thin, we inevitably end up cooking them past medium, which means that we want them to be nice and fatty to start. This'll help them stay juicy as they cook. Depending on exactly what part of the loin they're cut from, pork chops can behave quite differently. Center- or rib-cut chops will have a large eye of lean meat, with just a bit of fat surrounding it. Blade end chops will have meat from multiple different muscle groups, all interspersed with creamy white fat. These are the ones you're looking for. They boast more flavor and are juicier. If they're cut too thick, they can be tough and chewy, but when they're cut thin and cooked crisp, that's not an issue.
With acidic marinades, you have to be very careful to not over-marinate. But with a sweet-and-salty marinade like this, letting the pork sit is not much of a problem. Because it's so salty, the marinade acts as a brine, breaking down some of the pork's muscle structure and allowing it to maintain more juiciness as it cooks. About a half hour in the marinade is enough to make an appreciable difference, but if you're not in a rush, up to overnight will deliver pork chops with a smooth, juicy texture, almost like a good ham steak.
When ready to cook, I cook the chops over high heat on the grill (you could also use a grill pan indoors, though don't expect to get the same smoky, charred flavor), flipping them multiple times to encourage even browning. Because of the high sugar content of the marinade, the pork chops are particularly prone to charring. A little bit of this is not a bad thing. In fact, I feel that the pork should be black in a few spots around the edges and the fatty bits.
But don't go overboard. Use a two-zone fire, and be ready to shift the chops over to the cooler zone if they're browning too fast.
The pork chops are so thin, they're ready to come off the grill in just five or six minutes.
This is a dish in which the sauce is almost as important as the meat itself. Fortunately, this time, the legwork was already largely done for me. Our recipe for nuoc cham, the classic Vietnamese condiment made with fish sauce, lime juice, sugar, garlic, and chilies, forms the sweet, sour, and savory backbone of the dipping sauce. Typically, you'd mix that base with do chua, the pickled carrots and daikon you find stuffed into banh mi. But if you don't have the pickled version lying around, you can add julienned or grated fresh carrots and daikon to the sauce, with no major ill effect.
It's not traditional, but I like a bit of heat with my sweet-and-savory dishes, so I add a pinch of crushed chili flakes to the sauce as well.
Serve the pork chops hot on top of a pile of rice, with a side of sliced cucumbers, and pour that sauce on top. I know that in many cases in Japanese or Chinese dining, it's frowned upon to douse rice with sauce because that makes it difficult to pick up. I have no idea if it's equally taboo in Vietnam, but at my house, that rice is getting sauced.