This is restaurant-level beef & broccoli: tender flank steak and crisp greens tossed in a glossy soy-oyster sauce.
This Chinese restaurant classic comes together in three stages: marinating the beef, cooking the broccoli, and making the sauce.
The marinade uses cornstarch and baking soda to tenderize the beef. This technique is known as "velveting"—it's the secret to tender meat in fast-cooking Chinese dishes. Here, baking soda breaks down the fibers in the beef while cornstarch imparts a smooth, almost slippery texture. Without velveting, your beef will come out tough and chewy.
For crisp greens, cook your broccoli separately via blanching or steaming. Don't waste the stem by throwing it away! Remove the fibrous outer peel, slice the stem into thin planks, then use together with your florets.
Prepare flank steak: Clean steak and remove silverskin (the thin, silvery membrane) with a paring knife. Slice meat against the grain into thin strips. Transfer to a bowl.
Marinate meat: Combine the rest of the marinade ingredients in the bowl with the meat. Mix well until combined. Massage the marinade into the meat using clean hands. Leave for 30-35 minutes to tenderize.
Prepare broccoli: While marinating the meat, wash and clean the broccoli. Using a sharp knife, trim off the stem (don't throw it away!) and divide the broccoli into florets. Peel off the tough outer skin from the stem, then slice into ¼-inch thick rectangles.
Blanch broccoli: Bring a pot of water to a boil over high heat. While the water heats up, prepare an ice bath by combining water and ice cubes in a bowl. Once the water is boiling, blanch the broccoli until softened but still crisp, 2 minutes. Strain and transfer broccoli to the ice bath to prevent it from cooking further. (For steaming broccoli, check Notes.)
Cook beef: Heat ½ cup of oil in a wok or skillet over high heat. Once oil is shimmering, add beef and fry until lightly browned, 45 seconds to 1 minute. Remove beef from oil and set aside. Transfer remaining oil to a heatproof bowl to cool down, leaving 1 tablespoon of oil in the wok or skillet.
Make sauce: Add garlic and ginger to the wok or skillet. Cook aromatics, stirring constantly, until fragrant. Add water, soy sauce, rice wine vinegar, oyster sauce, and sugar. In a separate bowl, dissolve cornstarch in 1 tablespoon water to make a slurry. Add slurry to the sauce, then stir until well combined.
Toss beef and broccoli: Add beef and broccoli to the sauce. Toss and stir until both meat and vegetables are evenly coated. Transfer to a serving dish. To finish, drizzle with sesame oil and garnish with sesame seeds. Serve with hot steamed rice.
