Prepare and cook the shrimp. Marinate the shrimp with fish sauce, sugar, white pepper and starch for 10 minutes.
Prepare the vegetables. Wash all vegetables. String the snow peas. Both sides of the snow peas have a tough fiber. Slice the celery at an angle. Peel and slice the carrot on the diagonal. Slice the mushrooms. Be sure to chop all ingredients to the same thickness. Mince garlic and slice ginger.
Blanch the vegetables. In a pot or wok, bring water to a boil with salt and oil. Blanch everything in the same wok, adding in this order: celery and carrot for 30 seconds, then snow peas for 30 seconds, finally mushrooms for 10 seconds. All vegetables should be brightly coloured. Remove with slotted spoon and set aside.
Cook the chow mein. Cook noodles in vegetable water for 30 seconds and strain immediately into colander.
Make the sauce. Meanwhile, add water or unsalted chicken stock, fish sauce, Shaoxing wine, sesame oil, starch, sugar, salt and pepper into a bowl. Stir altogether.
Stir fry. Everything comes quickly in this step. In a pan or wok, over medium heat, add enough oil to cover the bottom. When the oil starts to shimmer, add noodles and fry until golden and crispy. You may need to do this in batches. Flip halfway through. Optional, place the crispy noodles on paper towels to remove any excess oil then, place crispy noodles on a plate. Set aside. Next, saute shrimp over medium heat until they turn white, about one minute. Set aside. Third, saute garlic and ginger until fragrant, about 30 seconds. Stir in blanched vegetables, about 10 seconds. Give the sauce a quick mix, then pour it in, and stir-fry for 20 seconds until sauce thickens. Add cooked shrimp and mix, about 10 seconds.
Assemble the dish. Pour the sauce and stir fried ingredients over crispy noodles. Enjoy! Serve immediately.