Preheat your oven to 375°F. Grease a 9x13-inch baking dish with butter or cooking spray.

Cook the tortellini according to package directions, reducing the cooking time by two minutes. Drain well and set aside.

Melt butter in a large saucepan over medium heat. Add minced garlic and sauté for about one minute until fragrant.

Reduce heat to medium-low. Add heavy cream and cream cheese to the pan. Whisk constantly until the cream cheese melts completely and the sauce becomes smooth.

Stir in one cup of Parmesan cheese and one cup of mozzarella cheese. Continue whisking until the cheeses melt and the sauce thickens slightly. Season with Italian seasoning, salt, and black pepper.

Remove from heat and fold in the cooked tortellini. Gently toss until every piece gets coated in the creamy alfredo sauce. Transfer everything to your prepared baking dish.

Sprinkle the remaining Parmesan and mozzarella over the top of your tortellini alfredo casserole. If using breadcrumbs, scatter them evenly over the cheese layer.

Bake for 20-25 minutes until the cheese melts, bubbles around the edges, and turns golden on top.

Let the tortellini alfredo casserole rest for five minutes before serving. Garnish with fresh parsley if desired.