01 -
Toss the sliced flank steak with soy sauce, cornstarch, and vegetable oil. Let sit at room temperature for 15 minutes while you prepare the vegetables.
02 -
Whisk together beef broth, soy sauce, oyster sauce, black pepper, ginger, garlic, and cornstarch in a small bowl until smooth.
03 -
Heat vegetable oil in a large skillet over medium-high heat. Add the beef in a single layer and cook for 1-2 minutes per side until browned. Remove to a plate.
04 -
Add the onion and bell peppers to the same skillet. Cook for 4-5 minutes, stirring often, until softened at the edges but still crisp.
05 -
Pour in the sauce and simmer for 1 minute until it starts to thicken. Return the beef to the pan and toss to coat in the glossy glaze.
06 -
Drizzle with sesame oil and serve immediately over steamed rice or noodles.