Preheat oven to 375F. Mix cream cheese, spinach, 1 cup mozzarella and 3 tbsp Parmesan until well blended; spread onto chicken breasts. Starting at one short end of each breast, roll up chicken tightly. Secure with wooden toothpicks. Set aside.
Beat egg in shallow dish. Mix remaining parmesan and cracker crumbs in seperate shallow dish. Dip chicken bundles in egg, then roll in crumb mixture. Place, seam side down in a 13x9 inch baking dish sprayed with cooking spray.
Bake 30 minutes or until chicken is done. Remove toothpicks. Serve topped with spaghetti sauce and remaining mozzarella cheese.