Preheat the oven to 350. Spray a 9×13 baking pan with nonstick spray.
Cut your chicken in to cubes.
In one bowl, whisk together the cornstarch, salt and pepper.
In another bowl, whisk the eggs till smooth.
Heat the oil in a large skillet.
Work with small batches of the chicken at a time. There should be room in the skillet to brown the pieces without them touching. Dip the pieces of chicken of chicken into the cornstarch to coat then dip into the eggs and place in the hot oil. Cook the chicken until the batter is browned on both sides but the chicken is not cooked through. Place the chicken in the prepared baking pan as you finish each batch. (Add oil in to the pan as needed between batches.)
For the sauce, whisk together the sugar, apple cider vinegar, ketchup, soy sauce and garlic salt in a bowl and then drizzle the sauce evenly over the chicken in the baking pan.
Bake for 20 minutes at 350 then raise the heat to 400, give the chicken a toss and bake for another 20 minutes until golden brown with crispy edges.
Remove from the oven and serve immediately over rice.