Jeyuk Bokkeum (Spicy Korean Pork Stir-Fry)

Which pork to buy: Choose a cut with some fat in it; lean slices turn dry and chewy in a hot pan. In the US, look for boneless pork shoulder, also sold as pork butt or Boston butt (it comes from the shoulder, despite the name), or shoulder blade steaks, which are easier to slice. In the UK, pork shoulder steaks are the easiest find. Skinless pork belly gives a richer result with crispier edges. Korean cooks mostly use apdari-sal (front leg and shoulder), moksal (collar) or samgyeopsal (belly). Lean loin or tenderloin works if you pull it off the heat as soon as the pink is gone.

Pre-sliced pork: To skip slicing, look in the meat case at a Korean or other Asian grocery store for pork shoulder already sliced thin, often labeled for bulgogi, or thin pork belly slices sold for hot pot. They are often frozen in rolls: thaw them in the fridge, pull the slices apart and pat them dry so they brown instead of steaming. Hot pot slices cook through in about a minute per batch.

Getting char without burning the sauce: When pork goes into the pan already coated in sauce, the sugar and gochujang touching the hot metal burn before the wet meat has time to brown. Searing the pork alone first and adding the sauce over medium heat at the end avoids that. Sticky, dark red-brown spots are what you want; Korean cooks call this smoky, seared flavor bulmat, literally "fire taste." Black edges and a sharp, acrid smell mean burnt sugar, which tastes bitter, so add a splash of water and lower the heat right away. If the pork gives off a puddle of liquid and simmers instead of sizzling, the pan was too full or not hot enough; keep cooking until the liquid boils off and the pork browns.

Checking doneness: The USDA's safe minimum for whole cuts of pork, such as chops and roasts, is 145°F (63°C) with a 3-minute rest. Stir-fry slices are too thin for a thermometer but heat through in a minute or two, so cook them until no pink remains outside or in the center; cut the thickest piece open if you are unsure. Slices thicker than 1/4 inch (6 mm) are worth checking with an instant-read thermometer. Wash your hands, knife and cutting board in hot, soapy water after handling raw pork.

Making it milder or hotter: This version is medium-spicy, but gochujang heat varies by brand (many tubs print a heat level), so taste the sauce first. For a gentler version, use 1 1/2 tbsp gochujang, skip the gochugaru and fresh chili, and add 2 tsp more soy sauce and 1 tsp more sugar to make up the lost salt and sweetness. For no heat at all, make the soy sauce style often called ganjang jeyuk bokkeum: skip the gochujang, gochugaru and fresh chili, use 4 tbsp (60 ml) soy sauce and 2 tbsp sugar, and keep everything else the same. It tastes close to our Beef Bulgogi. For more heat, add more gochugaru or use a serrano instead of the jalapeño.

Swaps: If you have no gochugaru, leave it out, since the gochujang carries the dish, or add 1 tsp sweet paprika (for color) and a pinch of cayenne (for heat). Do not swap in crushed red pepper flakes one for one, since they are much hotter. Use dry sherry in place of mirin, or skip it and add 1/2 tsp more sugar. Ground ginger (1/8 tsp) can replace the fresh. Zucchini, mushrooms or bell pepper strips can join or replace the cabbage. For gluten-free jeyuk bokkeum, use tamari or a soy sauce labeled gluten-free, and check the gochujang label, since many brands contain wheat.

Making it ahead: Many Korean home cooks marinate the pork instead, which seasons it more deeply but gives less char. Stir the sauce into the raw sliced pork, cover and refrigerate for 30 minutes to 24 hours. Cook it in two batches over medium-high heat, stirring often, until no pink remains, about 5 minutes per batch, adding a spoonful of water whenever the sauce sticks and darkens. Then return all the pork to the pan, add the onion, cabbage and carrot and stir-fry for 2 to 3 minutes, until the onion softens, then finish with the scallions, sesame oil and seeds as in the recipe. Marinated raw pork also freezes well, spread flat in a zip-top bag, for up to 3 months; thaw it in the refrigerator overnight.

Storage: Get leftovers into the fridge, in an airtight container, within 2 hours of cooking; they keep for up to 3 days. Warm them in a pan with a spoonful of water, or covered in the microwave, until steaming hot all the way through (165°F / 74°C).

Ways to serve it: Spooned over short-grain rice, often with a fried egg on top, it becomes jeyuk deopbap, a common Korean lunch (deopbap means rice with a topping). For ssam (lettuce wraps), set out leaf or butter lettuce, plus perilla leaves (kkaennip, often labeled sesame leaves) if you can find them. Lay a leaf in your palm, add a little rice, some pork and a dab of ssamjang, a thick dipping paste made from doenjang (fermented soybean paste) and gochujang, then fold it into one bite. Korean lunch restaurants often serve it with banchan (small side dishes) and a bowl of soup or stew, such as doenjang jjigae (soybean paste stew); at home, Easy Kimchi and a cool Korean Cucumber Salad add a tangy, crunchy contrast. Chopped leftovers make great fried rice; see our Kimchi Fried Rice for the method.