Over medium heat, add neutral oil to a pan and cook ground pork until the fat starts to render and meat loses pink color.
Add chopped shiitake mushrooms and stir to incorporate, the mushrooms will also release moisture so you want to sauté until it starts to evaporate.
Add scallion whites, ginger, white portion of scallions, then season with soy sauce and sugar, again stirring until liquid evaporates.
Mix all sauce ingredients in a separate bowl.
Boil noodles according to package instructions and blanch bok choy for 30-60 seconds.
Add the hot noodles to the sauce and mix, adding noodle water so that sauce coats noodles smoothly and evenly.
Plate with the pork mixture on top, bok choy, greens of scallions and drizzle of chili oil.