Cheesy Spinach Stuffed Meatloaf

Heat oven to 350ºF (175ºC). In large bowl, combine meatloaf ingredients, mixing lightly, but thoroughly. In medium bowl, combine filling ingredients; mix well. Set aside. Place beef mixture on waxed paper and pat into 14x10-inch rectangle. Spread filling over beaf, leaving 3/4-inch border about edges. Starting at short end, roll up jelly-roll fashion. Press beef mixture over spinach filling at both ends to seal. Place seam side down on rack in open roasting pan. Bake in oven 1 hour. Spread ketchup over loaf; return to oven and continue baking 15 minutes or until beef is no longer pink. Top loaf with 1/4 cup mozzarella cheese. Sprinkle with additional Italian seasoning, if desired. To serve, cut into 1-inch thick slices.