Bring a large pot of salted water to the boil. Add the dried wholewheat noodles and stir to prevent them from sticking together. Cook according to the packet instructions and drain well. Drizzle over a little oil and shake to prevent the noodles from clumping together.
Meanwhile, mix together all the sauce ingredients and set aside.
Heat 1 tablespoon of sunflower oil in a wok or large pan. Add in the broccoli, peppers and onion. Pour in the water to create steam and stir-fry for 3 minutes to soften the vegetables. Add in the sugar snap peas and baby corn and cook for a further 2 minutes.
Add the cooked, drained noodles to the wok and pour over the sauce. Mix well and heat through for 2 minutes.
Serve the noodles hot, garnished with the spring onions, peanuts and coriander.