Preheat the oven to 375°F so the dish bakes evenly and the cheese melts properly.
Mix the filling by combining chicken, bacon, ricotta, Parmesan, and seasonings until smooth, adding a little cream if needed.
Stuff the cooked jumbo shells with the filling, keeping them full but not overpacked to avoid tearing.
Make the Alfredo sauce by melting butter, adding cream, seasoning it, and simmering until thickened.
Assemble the dish by spreading sauce in a baking dish, arranging the stuffed shells, and covering them with the remaining sauce.
Top with mozzarella and bake for 25 to 30 minutes until melted, bubbly, and lightly golden.
Garnish and serve with fresh parsley, letting the dish rest briefly before plating.