In a bowl, toss the thinly sliced beef with soy sauce and cornstarch until well coated. Set aside to marinate for about 10-15 minutes.
Cook the lo mein noodles or spaghetti according to the package instructions. Drain and set aside.
Heat 1 tablespoon of vegetable oil in a large skillet or wok 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.
In the same skillet, add the remaining 1 tablespoon of vegetable oil. Sauté the sliced onion, minced garlic, carrots, bell peppers, broccoli, and snow peas until the vegetables are tender-crisp, about 5-7 minutes.
Return the cooked beef to the skillet with the vegetables.
ADVERTISEMENT
