Place soy sauce, vinegar and cornflour in a bowl. Marinade octopus for 20 minutes.
Prepare all ingredients and place in bowls near stovetop; you will need to work fast! Soak egg noodles for 2 minutes prior to cooking.
Heat 1 Tbls of each oil in a wok until smoking. Fry drained octopus for 10 seconds. Remove and wipe wok.
Heat remaining oil until smoking. Saute garlic, ginger and chilli until just starting to turn brown. Add sprouts, capsicum and onion and fry for 1 minute. Pour egg over the top and scramble by stirring.
Add egg noodles to wok, ensuring they do not clump together by stirring.
When noodles are almost cooked, place octopus back into the wok and combine.