Heat the wok/skillet to medium-high and add 2 tbsp oil; wait for 30 seconds.
Add garlic, onion, bell pepper and mushrooms; mix and stir. Cook for 2-3 minutes or until the onions becomes translucent.
Add bok choy and cook for 2-3 minutes or until the leaves become slightly wilted; mix and stir. Remove the cooked vegetables and set aside.
Add 2 tbsp oil to the wok/skillet. Place the marinated meat in and cook for 2 minutes or until no longer pink.
Place the cooked noodles in the wok/skillet. Pour the sauce on top of the noodles and mix until well coated.
Return the vegtables to the wok, toss until well mixed and then remove wok from heat.