In a bowl cover mushrooms with 1 cup (250 mL) boiling water; let stand for 20 minutes. Drain, reserving liquid. Slice mushroom caps thinly; set aside. Discard stems.
FOR CHICKEN: In a nonstick wok or large nonstick saucepan sprayed with cooking spray, cook chicken over medium-high heat for 4 minutes or until meat is barely cooked through. Add gingerroot and garlic and cook for 1 more minute. Set aside.
FOR PORK: In a nonstick wok or large nonstick saucepan sprayed with cooking spray, cook pork over medium-high heat for 4 minutes or until meat is barely cooked through. Add gingerroot and garlic and cook for 1 more minute. Set aside.
In a large pot, bring the stock and reserved mushroom liquid to a boil. Add the udon noodles and cook according to package directions.
Add the bok choy and snow peas to the pot and cook for 2-3 minutes, until tender-crisp.
Add the cooked chicken or pork and shrimp to the pot and heat through.
Stir in the bean sprouts and cook for 1 minute.
Garnish with green onions and parsley before serving.