In each bowl place a dash of soy sauce, dash of salt and pepper, good scattering of finely slices scallion greens
Bring a saucepan of water to a boil, and bring 1 1/4 cups soup stock per person to a boil in a separate pan at the same time
Add the noodles to the water and cook until tender. When noodles are nearly ready, add a portion of the boiling stock to each serving bowl. Add a portion of a cooked noodles to each serving bowl
Shell and devein the shrimp, then rinse thoroughly and shake dry. Place in a bowl, stir in 1/2 tsp salt and then the corn starch and egg white and mix well, set aside
Separate the green and white parts of the scallions, and cut them into 1 1/2-inch pieces. Discard any wilted leaves from the greens and, if you are using bok choy, cut a cross into each stem as you might with brussles sprouts, so they will cook quickly
Heat the peanut oil in a wok until it reaches 300 F. Strain any excess egg white form the shrimp, and then fry them briefly, stirring to separate, until they just turn pink; remove and set aside. Drain off all but 2 Tbsp of the oil
Add the scallion whites, garlic, ginger, and chili to the oil in the wok and stir-fry until fragrant. Add the shrimp and stir a few times. Pour in the stock and season with salt to taste. Add the bok choy or choy sam and the scallion greens, and continue to stir until they are cooked but still crunchy. Give the potato flour mixture a stir and pour into the middle of the wok, stirring briefly as the liquid thickens. Off the heat, stir in the sesame oil and pepper to taste, then spoon over the noodles you prepared above. Give the noodles a good stir before eating
Add black vinegar (lots of it for me) and extra chopped chilies and dig in baby!!!