In a large Dutch oven or wok, heat oil and stir-fry garlic, ginger, spring onions, chillies, mushrooms, chicken, prawns and sausage until prawns are pink and sausage is slightly browned. Stir in the sake and soy sauce and simmer 2 to 3 minutes. Cover and set aside.
Fill a large saucepan with water and bring to a rolling boil. Add noodles and cook over high heat for 2 minutes. Drain immediately and rinse with cold water.
Place the prawns mixture over medium heat and add the bean sprouts; saute for 2 minutes. Stir in the snow peas and saute 2 minutes. Stir in cooked noodles and toss until well mixed. Serve immediately.