Meat is precious and Buddhist traditions are strong in Vietnam, which is why dishes of beef are considered a luxury. Clever cooks cut tender, marbled cuts into small pieces so they soak up flavor, then cook them quickly and serve them hot with aromatic herbs. Here, the peppery, salty-sweet, juicy beef mingles with the light salad dressing to create a great sauce that pools on the platter, perfect for drizzling over rice. Watercress leaves warm and wilt under the Shaking Beef (so named for the back-and-forth shaking of the pan), while their stems remain crunchy. In the summer, sub cherry tomatoes for the radicchio. For a stunning appetizer, serve the sautéed beef with some fresh herbs and toothpicks for easy sharing.
How to Make It
Stir together oyster sauce, soy sauce, sugar, cornstarch, fish sauce, pepper, and garlic in a medium bowl. If a saltier finish is desired, add up to 1 1/2 teaspoons more oyster sauce. Add beef, toss well to coat, and let marinate 20 minutes at room temperature.
Rinse onions in a strainer under cold running water for about 10 seconds; set aside. Whisk together 2 tablespoons water, vinegar, sugar, salt, and pepper in a large bowl until sugar is dissolved. Add onion; top with watercress, radicchio, and herbs. Do not toss.
Heat a large, heavy skillet over high, and add oil. When oil is shimmering, carefully add beef in a single layer. Cook, shaking pan every 30 to 60 seconds, until seared on all sides and meat reaches desired degree of doneness, 3 to 4 minutes for medium-rare. Remove from heat. Quickly toss salad, and transfer to a platter or serving dish. Pile cooked beef and juices on salad, and serve immediately.