Ingredients:

1 lb flank steak, thinly sliced against the grain
2 tablespoons soy sauce
1 tablespoon cornstarch
1 tablespoon vegetable oil
1 large onion, thinly sliced
2 bell peppers (any color), thinly sliced
3 cloves garlic, minced
1 tablespoon ginger, minced
1/4 cup soy sauce
1/4 cup beef broth
2 tablespoons oyster sauce
1 tablespoon hoisin sauce
1 teaspoon sugar
1/2 teaspoon black pepper
1/4 teaspoon red pepper flakes (optional)
Cooked rice (for serving)
Green onions, chopped (for garnish)

Instructions:

Marinate the Beef: In a medium bowl, combine the sliced flank steak, 2 tablespoons soy sauce, and cornstarch. Mix well and let it marinate for 15 minutes.

Cook the Beef: In a large skillet or wok, heat the vegetable oil over medium-high heat. Add the marinated beef and stir-fry until browned and cooked through, about 4-5 minutes. Remove the beef from the skillet and set aside.

Stir-fry the Vegetables: In the same skillet, add the sliced onion and bell peppers. Stir-fry for 3-4 minutes until the vegetables are tender-crisp.

Add Aromatics: Add the minced garlic and ginger to the skillet and stir-fry for another 1-2 minutes until fragrant.

Prepare the Sauce: In a small bowl, whisk together the 1/4 cup soy sauce, beef broth, oyster sauce, hoisin sauce, sugar, black pepper, and red pepper flakes (if using).

Combine and Cook: Return the cooked beef to the skillet and pour the sauce mixture over the beef and vegetables. Stir to combine and cook for another 2-3 minutes until the sauce has thickened and everything is heated through.

Serve: Serve the pepper steak over cooked rice and garnish with chopped green onions.