Preheat oven to 350 degrees. Lightly grease a 9×13 inch baking pan.
Cook spaghetti according to package directions. Drain and place in a large bowl. Add cream cheese, Italian Seasoning, garlic, and heavy cream. Stir until cream cheese is melted and the spaghetti is thoroughly coated.
Add in the Alfredo sauce, chicken, and parmesan cheese. Toss to combine. Pour into the prepared pan and spread out to evenly fill the pan. Sprinkle with mozzarella cheese.
Bake at 350 degrees for 30 minutes until hot and bubbly. Serves 6-8.