Preheat oven to 450 degrees. Line pan with foil and spray with cooking spray. Mix together in gallon size zip bag, the oil, pepper, honey mustard, salt and rosemary. Half and quarter the potatoes, slice onion into bite size pieces and add both to the oil mixture. Toss until coated. Add turkey cutlets and toss until coated. Pour into lined pan and cook 35 to 40 minutes, or until potatoes are fork tender. Stir veggies every 10 to 15 minutes.