Preheat oven to 325 °F. Grease a square 8 x 8-inch baking dish and set aside. Bring a large pot of water to a boil. When boiling, sprinkle some salt, and then add dried cavatappi pasta. Cook until al dente (About 2 minutes less than the package directs).
Drain the pasta and drizzle with olive oil to keep it from sticking. Set aside to cool while preparing cheese sauce.
Melt butter in a saucepan over medium heat. Once the butter has melted, add flour, salt, and pepper. Whisk and cook for 2 minutes.
Gradually pour in cold milk and heavy cream, stirring constantly. Lower the heat to medium-low and cook for a few minutes until you see bubbles on the surface. Then continue cooking for 2 more minutes until the mixture is barely thickened.
Remove from heat and add 1 cup shredded cheese. Stir until melted.
Add the cooked cavatappi noodles and toss to coat.
Pour half of the mixture into the baking dish. Sprinkle 1/2 cup cheddar cheese over the top.
Add the remaining mixture and sprinkle with the remaining cheese.
Bake for 15-20 minutes or until the cheese has melted.
Sprinkle the optional chopped parsley, and serve hot with your favorite veggie or salad.