Combine the mozzarella cheese, mayonnaise, garlic powder, onion powder and Italian seasoning in a bowl, combine well.
Place bread halves on a sheet pan. Divide the mixture between the 2 halves of bread and spread evenly.
Divide the Parmesan cheese between the 2 halves of bread.
Bake in a 350 degree oven, until brown and bubbly ( 20 - 25 minutes. ). Can broil last few minutes of cooking time if desired.
Cut into slices and serve hot.