Preheat the oven to 375°F, and spray a 9x13-inch baking dish with cooking spray. Set aside.
Melt the butter in a medium skillet over low-medium heat. Add the garlic, and cook for an additional 30 seconds.
¼ cup unsalted butter, 1 tablespoon minced garlic
Whisk in the flour and cook for 2-3 minutes to remove all the raw flour taste. While whisking, slowly pour in splashes of heavy cream and milk until the mixture is smooth and free of lumps.
⅓ cup all-purpose flour, 2 cups heavy cream, 2 cups whole milk
Increase the heat slightly to medium, and heat until it begins to steam and thicken slightly. Don’t let it boil!
Add in a pinch of nutmeg if using, salt, and pepper.
Pinch nutmeg, Salt and pepper
Drop in bits of parmesan cheese, whisking between each addition. Make sure all the cheese melts before adding more cheese.
2 cups parmesan cheese
Place the cooked pasta and chicken into a large bowl. Then pour the cheese sauce into the bowl, and stir gently to coat.
16 ounces penne pasta, 4 cups cooked chicken
Transfer the mixture to the prepared baking dish, and top with mozzarella cheese.
1 ½ cups mozzarella cheese
Bake, uncovered, for 10-15 minutes until the cheese begins to brown and melt. Serve warm.
Scroll up and see the post for tips, storage information and FAQs.
Notes
*The calories listed are an approximation based on the ingredients in the recipe card and a serving size of 1 cup of pasta bake. Actual calories will vary.