Warm 1 tablespoon of vegetable oil in a wok or large skillet over medium-high heat.
Add the thinly sliced onions and cook until they start to soften, about a few minutes.
Stir in the minced garlic and sauté for another minute to release the flavor.
Toss in the carrots and Chinese cabbage, then pour in the remaining tablespoon of oil.
Stir everything together and let the vegetables cook down for a few more minutes.
Incorporate the sliced mushrooms and continue stirring as they soften for 2 to 3 minutes.
Splash in the shaoxing wine and mix to combine.
Add the cooked noodles and 2 tablespoons of the reserved pasta water, tossing gently.
Pour in the dark soy sauce, light soy sauce, hoisin sauce, oyster sauce, sugar, and salt.
Mix all ingredients thoroughly and taste; adjust seasoning if necessary.
Finally, fold in the scallions and give it one last toss before serving.
Serve immediately while the dish is hot and fresh.