At Lunar New Year celebrations, it’s traditional to serve long noodles, symbolizing a long life. Put the pork in the freezer 30 minutes before slicing; it’ll cut more easily and you’ll get thinner slices.
Soak mushrooms in about 2 cups hot water; set aside.
Bring a large pot of salted water to a boil. Add noodles and return to a boil. As soon as water boils, add 1 cup cold water; return to a boil. As soon as water boils again, add 1 more cup cold water. When it returns to a boil, drain and rinse with cold water. Set noodles aside.
Drain mushrooms, slice thinly, and set aside.
In a large wok or sauté pan, heat 2 tablespoons oil on high setting. Add half the scallions to pan and sauté until bright green and wilted, about 1 minute. Add pork and soy sauce; sauté, stirring often, about 2 minutes. Add carrots and salt to taste; cook, stirring often, about 2 minutes. Add bean sprouts; cook, stirring often, about 1 minute. Add mushrooms; cook, stirring often, about 1 minute. Add cabbage; cook, stirring often, about 1 minute, or until wilted. Remove pan from heat.
In a separate wok or sauté pan, heat remaining oil on high setting. Add garlic chives and remaining scallions; sauté until wilted. Season with salt and pepper. Add collected liquid from pan of cabbage and pork. Add cooked noodles and stir well; saute 2 minutes, or until heated through and well coated. Add the cabbage/pork mixture, and toss well to coat noodles.