I've had this recipe for probably forty years, so I have no memory about where I got it. It is absolutely scrumptions. I've used it for family meals but also for company. I like to use large pieces of the white meat.
Preheat oven to 400°F Beat eggs with salt and pepper. Combine Parmesan cheese with crumbs. Dip turkey pieces in egg mixture, then in crumb mixture. Place in a well-greased shallow baking dish. Bake at 400 for 15 minutes. Remove from oven and set aside.
Reduce oven temperature to 350°F
Heat oil in skillet, add onions and cook until very light brown. Stir in tomato sauce, wine, and oregano, and heat thoroughly. Pour over turkey. Arrange mozzarella slices on turkey.