Easy Gluten-Free Mac And Cheese

["Preheat the oven to 375u00b0 F.", "Spray a 9 x 13"" baking dish with cooking spray. Set aside.", "Using a cheese grater or food processor fitted with a grating attachment, grate the cheddar cheese. Set aside.", "Cut the cream cheese into 1/2"" cubes. Set aside.", "Place the noodles, 4 1/2 cups of milk, 2 Tbs. of butter, and 1/2 tsp. of salt in a large pot. Cover the pot with a fitted lid.", "Set the pot over medium-high heat and bring to a boil. Once boiling, immediately reduce the heat to medium-low so that the milk is at a low boil.", "Cook the noodles in the covered for 10 minutes until the liquid is mostly absorbed, stirring every few minutes.", "Turn of the heat and remove the lid from the pot. Add the cream cheese to the noodles and stir.", "Add the remaining milk, heavy cream, mustard powder, 1/2 tsp. of salt, and pepper to the pot. Stir.", "Add 8oz. (about 2 cups) of the cheddar cheese to the pot. Use a rubber spatula or wooden spoon to stir the noodles until the cheese is melted into a sauce.", "Pour the contents of the pot into the greased baking dish.", "Sprinkle the remaining cheese in an even layer over the top of the noodles. Transfer the dish to the oven.", "Bake the macaroni and cheese for 22-25 minutes, until the edges are bubbling and the top is lightly browned.", "Remove the dish from the oven. Allow it to rest for 15 minutes before serving."]