In a sauce pan, combine 1½ cups of water, sugar, vinegar, reserved pineapple juice, and orange food coloring. Heat to boiling. Turn off the heat. Combine ¼ cup cornstarch and ¼ cup water; slowly stir into sauce pan. Continue stirring until the mixture thickens.
In a small skillet with a tiny bit of cooking oil, saute the bell pepper, onions and pineapple till tender and crispy over high heat for about 2–3 minutes. Stirring frequently. Set aside.
Combine flour, 2 tablespoons of oil, 2 tablespoons of cornstarch, salt, white pepper, and egg. Add 1½ cups of water gradually to make a thick batter. Stir to blend thoroughly. Add the chicken pieces, and stir until coated.
Heat the oil in a sauce pan to 360 degrees. Fry the chicken pieces in hot oil until golden. Remove the chicken, and drain on a paper towel. Once drained, place them on a baking sheet or on a cake rack over a baking sheet in a cooler 200°-degree oven till ready to serve. (Placing on the cake rack prevents them from cooking more on the side lying on the cooking sheet)
Once all the pieces are cooked, and you are ready to serve, layer the green peppers, onion, and pineapple chunks, and the cooked chicken pieces on a platter. Pour the hot sweet and sour sauce over top.