2 tablespoons vegetable oil (or sesame oil for extra flavor)
1 medium onion, thinly sliced
1 red bell pepper, julienned (cut into strips)
1 green bell pepper, julienned
2 cloves garlic, minced
1 tablespoon fresh ginger, minced
2 tablespoons soy sauce
1 tablespoon oyster sauce
1 tablespoon hoisin sauce
1 tablespoon rice vinegar (or apple cider vinegar)
1/2 cup beef broth (or water if you prefer)
1 tablespoon sugar (optional, but it adds a nice balance of flavor)
1/2 teaspoon crushed red pepper flakes (optional, for some heat)
For Garnish (optional):
Sliced green onions
Sesame seeds
Instructions:
Prepare the beef:
Slice the flank steak thinly against the grain into strips, about 1/4 inch thick.
In a bowl, mix the soy sauce, cornstarch, rice wine, and white pepper. Toss the beef strips in this marinade, making sure they are evenly coated. Let it sit for about 15 minutes.
Make the sauce:
In a small bowl, mix together the soy sauce, oyster sauce, hoisin sauce, rice vinegar, beef broth, and sugar. Set aside.
Stir-fry the beef:
Heat a large skillet or wok over medium-high heat. Once hot, add 1 tablespoon of vegetable oil.
Add the marinated beef to the pan in a single layer and stir-fry for about 2-3 minutes until it’s browned but still tender. Remove the beef from the pan and set aside.
Cook the vegetables:
In the same pan, add the remaining tablespoon of oil.
Add the onions, red bell pepper, and green bell pepper. Stir-fry for about 3-4 minutes until the vegetables are just tender but still crisp.
Add the minced garlic and ginger and cook for another minute until fragrant.
Combine everything:
Return the cooked beef to the pan with the vegetables.
Pour the prepared sauce over the beef and vegetables. Stir everything together and cook for an additional 2-3 minutes until the sauce thickens slightly and coats everything evenly.
Finish and Serve:
Taste and adjust seasoning, adding salt, pepper, or more soy sauce if needed.
Garnish with sliced green onions and sesame seeds if desired.
Serve hot with steamed rice or noodles.
Tips:
For a bit of heat: If you like some spice, you can add sliced fresh chilies or a bit more red pepper flakes.
Other veggies: You can also add other vegetables like mushrooms, snap peas, or carrots for added texture and flavor.
Tenderizing beef: If you want extra tender beef, you can lightly pound the steak before slicing or use a meat tenderizer.