Prepare the marinade. Place the cornstarch, soy sauce, oyster sauce, black pepper and rice wine vinegar in a large bowl. Stir well until blended together.
Place the sliced chicken in the bowl with the marinade, and use your hands to massage the chicken with the marinade until the meat is well coated. Let it soak for at least 25 minutes, in a covered container in the refrigerator.
In a small bowl, prepare the sauce by combining the cornstarch, soy sauce, chicken stock, oyster sauce, brown sugar, freshly grated ginger, and black pepper. Stir, then set aside.
While the chicken is soaking, cook the Chinese egg noodles according to the package instructions. Drain the noodles and then rinse them with cool tap water, and add a little vegetable oil. Fluff and toss the noodles to prevent clumping.
Place a wok on high heat, and add about 2 tablespoons of oil, swirling it around to coat the sides of the pan. Once the oil is hot to the point of smoking, place the chicken strips in the pan and cook for about 2 minutes, until just cooked through. Remove the chicken from the wok and set it aside.
Stir-fry the broccoli, mushrooms, carrots and onions, stirring constantly with a wooden spoon for about 5 to 8 minutes until the onions are translucent. Add 1/2 cup of water, cover, and steam for 3 minutes. Set the cooked vegetables aside.
Bring 1/2 cup of water to a boil in the wok, and use a wooden spoon or spatula to deglaze the pan. Pour off the liquid and wipe the wok dry with paper towels. Return the wok to the heat, add 2 tablespoons of oil, and swirl the wok to coat the sides with oil.
When the oil gets hot to the point of smoking, add the shrimp. Let the shrimp cook on one side until it turns pink before flipping it over to the other side and letting it cook.
Return the chicken and vegetables to the wok, and toss to combine with the cooked shrimp.
Create a well in the middle of the ingredients and pour the sauce in, then stir well until the sauce thickens, keeping it relatively confined to the well in the center of the pan. Add the cooked noodles to the well and coat them with the sauce, using chopsticks or a fork to toss and separate them if they are sticking together.