Preheat oven to 350 degrees.
In a large bowl combine, meatloaf mix and all the other ingredients, except marinara sauce. Mix well until combined.
Using a loaf size baking pan, spread the marinara sauce on the bottom of the pan.
Place meatloaf mixture on top of sauce and form into a loaf.
Bake for 50 minutes.
Remove from oven and add the 5 slices of mozzarella cheese to the top of the meatloaf. Covering the whole loaf.
Return to oven and bake another 10 minutes or until cheese is nicely melted.
Remove from oven and let cool for 5 minutes before serving.