Bring 1L water to boil. Blanch bean sprouts and then rinse them in cold water and drain.
Mix the soy sauces, sesame oil, salt, sugar, wine and white pepper in a small bowl and set aside.
In another pot, bring water to boil. Boil the dried noodles for 2 minutes. Rinse in cold water and set aside.
Heat wok over high heat and add 1 tbsp of oil to coat the wok.
Spread the noodles in a thin, even layer on the wok and tilt the wok in a circular motion to distribute the oil and crisp the bottom layer of the noodles evenly. It should take about 5 min for the first side.
Flip the noodles over,add another tbsp of oil around the perimeter of the wok, and let the other side crisp up. Don’t stress if you cannot turn the noodles over in one shot. The goal is to get an even crispness and to dry out the noodles during this cooking stage.
Set the noodles aside on a plate.
Heat the wok over high heat. Add 1 tbsp oil and half of the scallion to the pan. Cook for about 15 secs. Next, add the noodles to the wok and toss them well, breaking up the noodles so they are not all in one big clump.
Add the soy sauce mixture and toss continuously for a couple of minutes. Keep the heat on high.
After the noodles are uniformly brown, add the bean sprouts and toss. Add the rest of the scallions and toss the mixture for another 1-2 min until you see the bean sprouts just starting to turn transparent. You want the sprouts to be cooked but still crunchy.
Plate and serve. Garnish with fried shallotsand baby chye sim.