Get Ready: Preheat your oven to 375°F (190°C). Lightly spray a 9x13-inch baking dish with nonstick spray.
Mix the Creamy Base: In a large mixing bowl, combine the softened cream cheese, sour cream, heavy cream, mayonnaise, minced garlic, salt, and pepper. Stir until everything is wonderfully smooth and well-blended.
Add the Good Stuff: Now, fold in your shredded chicken, well-drained spinach, chopped artichoke hearts, and grated Parmesan cheese. Give it a good mix to ensure all ingredients are evenly coated in the creamy sauce.
Assemble the Casserole: Pour this delicious mixture into your prepared baking dish, spreading it out evenly.
Cheesy Topping: Sprinkle the shredded mozzarella cheese generously over the top.
Bake to Perfection: Bake for 20 minutes at 375°F (190°C). Then, increase the oven temperature to 400°F (200°C) and bake for another 5 minutes, or until the mozzarella is beautifully golden and bubbly.
Serve & Enjoy: Let the casserole cool for a few minutes before serving. This hearty and healthy dish is perfect for a delicious meal!