This flank steak stir fry is my go-to pepper steak recipe when I want takeout flavor without the takeout wait. You get tender slices of beef, crisp bell peppers, and onions tossed in a rich, glossy black pepper sauce that’s savory, a little spicy, and packed with umami from oyster sauce, soy sauce, ginger, and a splash of Shaoxing wine. The best part is how fast it is, once everything’s sliced, it cooks in under 20 minutes and tastes like a legit restaurant stir fry.