Start by thinly slicing the flank steak against the grain. This technique ensures each bite is tender. Combine the beef slices with water, cornstarch, vegetable oil, kosher salt, and ground white pepper in a mixing bowl. Let it marinate for at least 30 minutes. This step helps create that melt-in-your-mouth texture we all love.
In a separate bowl, whisk together the chicken broth, cornstarch, dark soy sauce, regular soy sauce, brown sugar, toasted sesame oil, and white pepper. This delightful concoction is the heart of the dish. It’ll thicken as it cooks, enveloping the beef and broccoli in that mouthwatering sauce.
Heat 2 tablespoons of vegetable oil in a large skillet or wok over medium-high heat. Add the broccoli florets and stir-fry for about 2-3 minutes until they turn bright green and tender-crisp. Remove the broccoli from the skillet and set it aside. Nothing beats the beautiful green color of perfectly cooked broccoli!
Add the remaining tablespoon of vegetable oil to the skillet. Increase the heat to high and add the marinated beef. Sauté until it's browned and cooked through—about 3-4 minutes. The aroma will be incredible; you can practically taste it through the air.
Once the beef is cooked, toss in the minced garlic, ginger, and the broccoli you set aside earlier. Add the Shaoxing rice wine and oyster sauce. Pour the prepared sauce over everything, stirring to coat evenly. Let it cook for an additional minute so that the flavors can meld and deepen.
Finish with chopped green onion and a sprinkle of chili flakes for a subtle kick. Serve hot over steamed rice or your preferred side. Watch people’s eyes widen in wonder at your culinary prowess as they dig in.