Preheat oven to 325 degrees.
Rinse chicken in water and cut into 1 inch cubes. Place cornstarch and eggs in separate bowls.
Toss several pieces of chicken into the cornstarch to coat and then dip them in the eggs.
Set chicken pieces aside on a plate and repeat until all pieces have been coated.
Heat ¼ cup oil in a large pan and cook your chicken for a few minutes on each side until they are slightly browned but not cooked all the way. Place the chicken in a greased 9x13 pan. Set aside.
For the Sauce: Combine Pineapple juice, 2/3 cup water, vinegar, sugars, salt, soy sauce and Ketchup in a medium pot and bring to a boil.
Thicken sauce with cornstarch mixed with ¼ cup water stirring occasionally. Add desired amount of pineapple chunks and any optional ingredients. Pour evenly over the chicken.
Bake for half hour turning the chicken at 15 minutes. (NOTE: I like to leave a little sauce for dipping egg rolls or cream cheese wont tons. YUM!)