In a large bowl: add chow mein noodles, boiling water and cook for 15 seconds or follow the package recommendation cook time. Drain and set aside.
Heat a pan up to medium-high. Add 2 tbsp oil and wait for 30 seconds. Add marinated steak, stir continuously and cook for 3-4 minutes or until ~75% of the meat is medium to well done. Transfer the steak to a plate and set aside.
Add 2 tbsp of oil, sliced onions and minced garlic. Cook and stir for 1 minute or until fragrant. Add julienne carrots and cook for 1 minute. Add baby bok choy and toss everything together. Cook for 2 minutes.
Add chow mein noodles and sauce on top. Gently toss the noodles with the sauce. Add garlic chives, mung bean sprouts, steak and mix everything together. Remove the pan from the heat.