In a wok, combine the chicken stock, quartered lemon, parsley stalks and thyme. Place the wok over medium-high heat and bring the stock to a boil. Place the filets of orange roughy in the bamboo steamer. Sprinkle the filets with salt and pepper.
Place the bamboo steamer over the boiling liquid in the wok. Cover the steamer and steam the fish for 4 to 6 minutes depending on thickness of filets, or until the fish is opaque and just cooked through. Once the fish is cooked, remove the steamer from the wok. In a large saucepan, bring 2 cups of water to a boil over high heat.
Strain the stock from the wok into the saucepan of boiling water. Return the liquid to a boil. Add the noodles to the boiling liquid and cook for 4 to 5 minutes or until al dente, stirring often. Heat 2 tablespoons of olive oil in the wok over medium-high heat. Swirl the wok to coat with the oil.
Add the asparagus and morels and stir-fry for 2 to 3 minutes. Add the garlic to the wok and sauté for 1 minute. Sprinkle the lemon zest and lemon juice over the vegetables and season with salt and pepper.
Toss the stir-fried vegetables with 3 tablespoons of the noodle cooking liquid. Remove from heat. Strain the noodles from the cooking liquid, then season the noodles to taste with salt and pepper. Toss the noodles with 1 tablespoon of olive oil.
Using a two-pronged carving fork, twist the noodles around the fork and divide them among 4 plates. Place 1 orange roughy filet over each plate of noodles. Divide the stir-fried vegetable among the 4 plates.