Preheat oven to 350�. Combine cranberries, apples and walnuts in a medium glass bowl. Place breasts in a 13x9" baking pan. Top each breast with 1/3 cup filling. Bake for 30 minutes, or until chicken is no longer pink inside. Top each breast with 1/4 cup cheese. Bake for an additional 5 minutes, or until cheese has melted.