Boil the noodles in salted water until just tender (about 3–4 minutes). If making ahead, drain and rinse under cold, running water in a colander. Cook up to 3 hours ahead of time.
Put the grated ginger, water, and sweet chilli sauce into a saucepan and stir together over a medium heat for 1 minute. Add the hot noodles and toss in the sauce for a couple of minut