Phat ka-phrao is a ubiquitous street dish in Thailand, where cooks wielding woks will rapidly stir-fry sliced or minced meat flavored with garlic, shallots, fish sauce, and fiery Thai bird chilies, finish it off with a big handful of holy basil, and serve it with rice and perhaps a fried egg on top. Unless there's running water nearby, you'll probably eat it off of plates wrapped in the world's thinnest plastic bags (designed to be slipped off and discarded after use, like a plate condom), knees bent and back hunched, over a small plastic table. The only things thinner than those plastic bags are the napkins that disintegrate as you try to wipe the sweat from your brow.
Back in the United States, you can walk into any Thai restaurant and order phat ka-phrao off the menu, but you're unlikely to actually get it. Instead of the spicy, almost medicinal flavor of jagged-edged, fuzzy-leafed holy basil (ka-phrao), you're going to taste the sweet, anise-like flavor of Thai purple basil (bai horapha). Holy basil is difficult to come by 'round these parts.
Now, I could let this unfortunate state of affairs drive me to great lengths—literally—in search of the few leaves of holy basil that make their way to the Bay Area so that I might be able to recapture some of that Thai flavor. Instead, I generally choose to accept the fact that phat bai horapha is not phat ka-phrao, but it's still darned delicious in its own right. Even in Thailand, stir-fries with purple basil are commonly served, so we don't have to lose out on the authenticity points.*
Just make sure not to call your stir-fry made with purple basil "phat ka-phrao," lest Leela Punyaratabandhu, of the fantastic Thai recipe blog SheSimmers.com, get on your case.
Pounding Out Flavor
When I make the dish at home, it starts the way most Thai recipes do: with a mortar and pestle. Using a mortar and pestle to grind up garlic and chilies is not only more efficient than using a food processor—it's much easier to clean the two simple parts than to take apart my food processor, with all its nooks and crannies—but also produces better flavor.
Whether you're making guacamole or pesto, in test after test we've found that the crushing action of the pestle releases more flavor than the chopping of a food processor. I like to use a heavy granite one—its weight does most of the work for me.
To really effectively grind fibrous vegetables, you need to add some kind of abrasive. In most cases, that's salt, but here I use sugar. Palm sugar, if you can find it (it has a faint caramel-y flavor that does well in savory dishes), though unrefined cane sugar works fine in its place. With the abrasive, it takes only a minute or so of pounding and grinding to get the chilies and garlic worked into a fine paste. I use a dash of fish sauce to loosen it up.
Many Thai stir-fries begin with frying fresh aromatics in oil before adding your protein and tossing it all together. This is in contrast to Chinese-style stir-fries, which typically use much higher heat—hot enough that the aromatics would burn before your meat even got to the pan. I use the Thai oil-infusing technique from time to time, particularly for dishes featuring ground meat, in which the aromatics and sauce can really soak that meat in flavor.
But for recipes like this one, where the meat is sliced, I actually prefer to go with the more Chinese approach, which gives the meat a chance to really brown and bring some extra flavor of its own.
I start by thinly slicing beef—flank, skirt, hanger steak, and flap meat all make great stir-fries—against the grain in order to shorten its muscle fibers. I then marinate these slices with fish sauce, soy sauce, and a bit of sugar. The fish sauce and soy sauce are powerful sources of glutamic acid, which enhances the savoriness of the beef. Soy sauce also contains proteases—enzymes that can tenderize meat (though, if sliced thin, the meat should be plenty tender to begin with). The sugar is mainly there to help the beef get color a little more quickly when it hits the pan. (Don't forget: We've already got some palm sugar in the sauce to balance out the heat of the chilies.)
The real key to a successful stir-fry is to limit yourself to batches that your stovetop can handle. For instance, I know that if I try to add more than around a half pound of thin-sliced beef to my wok all at once, it'll instantly cool down, causing the meat to steam instead of brown. Working in batches, spreading the beef out, and allowing the wok to reheat in between are the secrets to good stir-fries on a home range. (Check out some more wok basics here.)
Once both batches of beef are browned, I wipe out the wok and reheat it for the final steps of the stir-fry. The beef goes back in, along with sliced aromatics—shallots, more garlic, and more chilies. (Yep, we're doubling up on chili and garlic flavor here—the sliced version of each has a different flavor from the pounded version.) This dish doesn't typically contain makrut lime leaf (from a wrinkly Asian lime often sold as "kaffir" lime in shops), but I love the aroma so much that I can't resist adding some, sliced into hair-width slivers.
As soon as my aromatics are, well, aromatic, and my beef is as browned as I'd like it to be, I add in the chili/garlic sauce. It should very rapidly reduce to a thin glaze (we're going for moist-but-not-saucy here). And we're finally at the moment when the fate of the dish is about to be decided. Will we get spicy, medicinal, and oh-so-rare phat ka-phrao, or will we get licorice-scented, easy-to-love and easy-to-source phat bai horapha?
I think we already know the answer to this one. My big ol' handful of Thai purple basil goes into the wok. A couple of tosses, a pinch of salt for seasoning, perhaps some extra lime leaf threads and fried shallots to garnish, and we've got a delicious (and authentic!) Thai meal in about 15 minutes.
This is just one of the many reasons I love my wok.