Mix vinegar, soy sauce, tomato ketchup, orange juice and honey together. Add the cornflour and stir until well combined.
Heat the oil in a non-stick frying pan and stir fry the chicken strips for 3-4 minutes. (If you don't use a non stick pan the chicken will stick to the pan).
Add the vegetables and stir fry for 4-5 minutes.
Add the cornflour mixture and bring to a boil.(Another tip-Don't use an overly large pan like I did or you will find the cornflour mix spreads too thin and there won't be enough liquid cook the vegetables.).
Meanwhile prepare the noodles according to the packet instructions, drain and add to the pan along with the sesame seeds. Mix well.