From: A Very Chinese Cookbook
Cut beef into 4 equal wedges. Transfer to plate and freeze until very firm, 20 to 25 minutes. Meanwhile, prepare gai lan: separate stalks; slice leaves crosswise into 1 ½-inch strips. Set aside. When beef is firm, stand 1 piece on its side and slice against grain, ¼ inch thick. Repeat with remaining pieces. Transfer to bowl. Add 1 teaspoon Shaoxing wine, 1 teaspoon soy sauce, and 1 teaspoon cornstarch and toss until beef is evenly coated; set aside.
In second bowl, whisk together ½ cup broth, oyster sauce, ½ teaspoon sesame oil, remaining 4 teaspoons Shaoxing wine, remaining 2 teaspoons soy sauce, and remaining 1 teaspoon cornstarch; set aside. In third bowl, combine 4 teaspoons vegetable oil, ginger, and ¼ teaspoon garlic.
Heat empty 14-inch flat-bottomed wok over high heat until just beginning to smoke. Drizzle 1 teaspoon vegetable oil all around perimeter of wok and heat until just smoking. Add gai lan stalks and cook, stirring slowly but constantly, until spotty brown and crisp-tender, 3 to 4 minutes; transfer to separate bowl.
Add remaining 1 teaspoon sesame oil, remaining 1 teaspoon vegetable oil, and remaining ½ teaspoon garlic to now-empty wok and cook, stirring constantly, until garlic is fragrant, about 30 seconds. Add gai lan leaves and cook, stirring frequently, until vibrant green, about 1 minute. Add remaining ¼ cup broth and cook, stirring constantly, until broth evaporates, 2 to 3 minutes. Spread mixture evenly in serving dish.
Add ginger-garlic mixture to now-empty wok and cook, stirring constantly, until fragrant, about 30 seconds. Add beef mixture and cook, stirring slowly but constantly, until beef is no longer red, about 1 minute. Add broth and oyster sauce mixture. Cook, stirring constantly, until sauce thickens, 30 to 60 seconds. Place mixture on top of leaves. Serve.
