1. Preheat oven to 350 degrees Fahrenheit (180 degrees Celsius).
2. Pour Italian dressing over chicken and then dip into cornflake crumbs.
3. Spray an oven-to-tableware dish with cooking spray and place cutlets in the dish. Cover and bake for 15 minutes.
4. Meanwhile, heat oil in a frying pan and sauté onions until golden. Add in diced pastrami and sauté five minutes more. Add duck sauce to the pan and cook until it boils.
5. Pour pastrami mixture over cutlets and bake, uncovered, for another 10 minutes.