Instructions

• Trim any excess fat from the flank steak, place it in the freezer for a few minutes to firm (optional), then slice the steak across the grain as thinly as possible. Put the sliced beef in a medium bowl.
• In a small bowl, whisk together 6 tablespoons soy sauce, 4 teaspoons cornstarch, 2 tablespoons water, and 1 teaspoon granulated white sugar. Pour this mixture over the beef and stir to coat. Set the marinated beef aside while you prepare the vegetables.
• Heat a wok or large skillet until very hot, then reduce the heat to medium. Add 1 tablespoon vegetable oil. Add 1 medium thinly sliced onion, 2 medium thinly sliced bell peppers, 1 cup sliced mushrooms, 1 cup sliced zucchini, and 1 medium thinly sliced carrot. Stir-fry the vegetables for 2 to 3 minutes, keeping them moving so they become crisp-tender and do not brown. Transfer the vegetables to a plate and set aside.
• Return the pan to high heat. Add the remaining 2 tablespoons vegetable oil and 2 teaspoons grated fresh ginger. Add the marinated beef to the pan and stir-fry, breaking up any pieces, until the beef separates and just begins to change color.
• Add the cooked vegetables back into the pan with the beef. Stir to combine and stir-fry about 1 minute more, until everything is heated through and the beef is cooked to your liking. Remove from heat.
• Serve immediately, with cooked rice if desired.