?1 1/2 pounds boneless beef short ribs, trimmed and sliced about 1/8 inch thick (see note)
Kosher salt and ground black pepper
1/4 cup fish sauce
1/4 cup lime juice, plus lime wedges to serve
3 tablespoons packed brown sugar
2 tablespoons peanut oil, preferably toasted, plus more to serve
1/2 small head red cabbage, finely shredded (about 4 cups)
1/2 English cucumber, halved lengthwise, seeded and thinly sliced on the diagonal
1 jalapeño chili, stemmed and sliced into thin rings
4 scallions, thinly sliced on the diagonal
1/4 cup roasted peanuts, chopped
In a medium bowl, toss the beef with 1/2 teaspoon salt and 1 teaspoon pepper. In a large saucepan, stir together the fish sauce, lime juice, sugar, oil and 1/4 cup water.
Bring to a simmer over high, then add the beef and cook, stirring constantly, until the meat is no longer pink, 2 to 3 minutes; the beef will release liquid as it cooks. Remove the pan from the heat and let stand for 10 minutes.
Meanwhile, in a large bowl, combine the cabbage, cucumber and 3/4 teaspoon each salt and pepper. Toss the vegetables with your hands, rubbing in the salt, until they just begin to wilt. Using a slotted spoon, transfer the beef to the bowl with the vegetables, then add the chili and scallions.
Add 1/4 cup of the beef cooking liquid and toss to combine. Taste and, if desired, toss in additional cooking liquid 1 tablespoon at a time until the salad is dressed to your liking. Transfer to a serving bowl, then top with the peanuts and drizzle with additional oil. Serve with lime wedges.