Combine ingredients for the sauce in a mixing bowl and whisk well. Chop chicken into small cubes, discarding fat if any, and add it to the sauce. Stir and let it marinade for 15 minutes.
(If you wish to cook it later, make sure to cover it well and refrigerate for a few hours or overnight.)
While chicken is marinading, cook noodles according to the package instructions, strain and set aside. Chop and slice vegetables and set them aside.
Preheat a large cooking pan (or a wok if available) over medium heat. Add canola oil and sesame oil.
Take out chicken (save marinade) and cook it until about half way done, stirring and turning it over as it cooks.
Add veggies, stir and cook until veggies start to soften.
Pour in marinade and cook until chicken is done and veggies are tender, stirring once in a while. Make sure sauce simmers for a few minutes since it contained raw chicken.
Once everything is cooked, add cooked noodles and stir until everything is evenly incorporated.
Garnish with extra diced scallions and sesame seeds.