Best-Ever Pepper Steak

1 pound beef sirloin, thinly sliced
1 red bell pepper, thinly sliced
1 green bell pepper, thinly sliced
1 small onion, thinly sliced
2 cloves garlic, minced
2 tablespoons vegetable oil
1 tablespoon soy sauce
1 tablespoon hoisin sauce
1 teaspoon cornstarch
1/4 teaspoon ground black pepper
1/4 teaspoon salt
Heat a wok or large frying pan over high heat. Add the oil and swirl to coat the pan.
Add the beef to the pan and stir-fry for 1-2 minutes, or until it is browned. Remove the beef from the pan and set it aside.
In the same pan, add the bell peppers, onion, and garlic. Stir-fry for 2-3 minutes, or until the vegetables are tender.
In a small bowl, mix together the soy sauce, hoisin sauce, cornstarch, black pepper, and salt.
Return the beef to the pan and add the sauce mixture. Stir-fry for an additional 1-2 minutes, or until the sauce has thickened and the beef is cooked to your desired level of doneness.
Serve the pepper steak over rice or noodles, garnished with chopped green onions if desired. Enjoy!