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)