In a ziplock bag, mix together flour and cornstarch with a pinch of salt, and set aside.
In a medium bowl place chicken pieces season lightly with salt and pepper.
Crack the egg over and mix with the chicken.
Add chicken pieces to the bag in small batches and shake to coat, take chicken out shake off excess flour and set aside.
Add chicken to the bag a little at a time and shake again until evenly coated. Add more of the 74/25 flour to cornstarch mixture if needed.
Add oil to a wok or large skillet and heat on medium high.
Add chicken, working in batches, and fry for about 2 minutes each side or until crispy golden brown.
Remove and place on a baking sheet lined with paper towels.
Continue until you are done with the whole batch, do not cram the wok or it will steam rather than fry.
Add a little bit more of oil if needed to the same wok
Add onions and sautéed for 1 minutes then add garlic, pineapple and bell pepper.
Continue to cook for another 1-2 minutes until pineapples and pepper is warm but still crisp.
Add the fried chicken back then pour in the chili sauce.
Stir to combine well then turn heat off.
Serve sprinkled with some sesame seeds and chopped green onions.