1.In a bowl, cover noodles with boiling water. Stand for 5 minutes. Drain, rinse and set aside. Noodles should be tender but firm. Repeat with fresh boiling water if necessary.
2.To make dressing, combine all ingredients in a bowl. Toss noodles with vegetables, herbs and dressing and set aside.
3.Heat a large non-stick wok or frying pan on high. Stir-fry beef quickly, until colour changes. Pile beef over noodles and serve topped with extra mint, coriander leaves, and peanuts, if desired.