1. Preheat the Oven and Prepare the Baking Dish: Start by preheating your oven to 375 F (190 C). Lightly grease a 9×13-inch baking dish with cooking spray to prevent sticking. This ensures easy cleanup later.

2. Cook the Tortellini: Bring a large pot of salted water to a boil. Add the refrigerated cheese tortellini and cook according to package directions, usually 2-3 minutes, until al dente. Drain the tortellini well and set aside. Do not overcook, as it will continue to cook in the oven.

3. Combine the Sauce Ingredients: In a large bowl, whisk together the jarred Alfredo sauce and heavy cream until well combined and smooth. This creates the rich, creamy base for your bake.

4. Assemble the Bake: Add the cooked tortellini and shredded or diced cooked chicken to the bowl with the Alfredo sauce mixture. Gently toss everything together until the tortellini and chicken are evenly coated in the sauce.

5. Transfer to Baking Dish and Top with Cheese: Pour the tortellini and chicken mixture into the prepared 9×13-inch baking dish. Spread it out evenly. Sprinkle the shredded mozzarella cheese and grated Parmesan cheese over the top of the mixture.

6. Bake Until Bubbly and Golden: Place the baking dish in the preheated oven and bake for 20-25 minutes, or until the cheese is melted and bubbly, and the edges are lightly golden brown. The internal temperature of the dish should be hot throughout.

7. Rest and Serve: Carefully remove the baking dish from the oven. Let it rest for 5 minutes before serving. This allows the sauce to set slightly and prevents it from being too runny. Garnish with fresh chopped parsley, if desired, for a touch of color and freshness.