Sprinkle the chicken breasts with salt and pepper.
In a bowl, scoop out the flesh of the sweet potato and mix it with the chevre. Line the bottom half of the chicken opening with the apple and pile on some of the sweet potato-chevre mixture.
Carefully wrap the chicken breasts closed with two pieces each of overlapping prosciutto, making sure the end is under the chicken.
Place on the baking sheet topped with rosemary and roast for 15 minutes, or until a meat thermometer inserted into the centre of the chicken reads 165 F. Enjoy!