Shanghai Fried Noodles (上海粗炒面)

Add the shiitake mushrooms into a medium bowl and pour hot water to cover. Soak until turning tender throughout, 15 minutes or so. Drain and slice the mushrooms into strips.
Combine the pork with Shaoxing wine, light soy sauce and cornstarch in a small bowl. Mix well.
Combine all the sauce ingredients in a small bowl.
Boil the noodles until al dente, 1 minute less than the package instructions call for. Drain, rinse with cold water to stop cooking, drain again and set aside.
Heat 1/2 tablespoon of oil in a large skillet over medium-high heat until shimmering. Spread the pork without overlapping. Cook for 1 minute until the bottom side is cooked, then stir a few times until turning white throughout. Transfer to a plate.
Add the remaining 1 1/2 tablespoons oil to the skillet, the scallion whites and shiitake mushrooms. Stir for 1 minute to release fragrance. Add the noodles. Toss with a pair of tongs to coat with oil. Pour in the sauce and toss again until the sauce coats the noodles evenly.
Add the bok choy whites. Stir to mix well. Cover the pan and let steam for 2 minutes. Add the bok choy greens, scallion greens and the cooked pork. Toss to mix well. Cover the pan and cook for another 1 to 2 minutes, until the bok choy has fully softened. Lower the heat and taste the noodles carefully. Adjust seasoning by adding a pinch of salt if needed. Transfer everything to a large platter and serve hot.