Put a large pan of water on to boil, then add the noodles. Boil for 4 minutes or until just tender.
Heat both of the oils in a large saucepan or wok, add the garlic and stir-fry for about 30 seconds.
Add the chicken and stir-fry for 5 minutes or until cooked. Remove from the pan with a draining spoon and set aside.
Add the pepper and stir-fry for 4 minutes, then add the sweetcorn and stir-fry for 1 minute. Add the spring onions and stir-fry for 1 minute. Return the chicken and noodles to the pan. Add the soy sauce and heat through, tossing to mix for 2 minutes.