Split the chicken breast halves lengthwise to create two thin cutlets for each breast. Set aside. Line a cookie sheet or baking pan with aluminum foil. Spray with non-stick vegetable spray. Set aside.
In a shallow pan or plate, combine the all-purpose flour and ginger sugar. Stir to combine. Thoroughly coat each chicken breast cutlet with the flour mixture. Set aside.
Heat a large skillet over medium-high heat. Spray the skillet with non-stick vegetable spray. Place the several cutlets in the pan and cook until browned. Spray each cutlet with non-stick vegetable spray and turn to brown on the second side. Transfer finished cutlets to the prepared baking pan. Repeat with remaining cutlets.
In a medium saucepan, combine the soy sauce, corn starch, olive oil and reserved pineapple liquid. Whisk until corn starch is completely dissolved. Add the crushed pineapple and stir to combine. Cook over medium heat until thickened.
Spoon the pineapple sauce over the chicken and top with the sliced green onions. Bake for 15 minutes.
Preheat oven to 350 degrees Fahrenheit.