Preheat your oven to 350°F (175°C) and grease a 9x13-inch casserole dish with butter or cooking spray.

In a large pot, bring salted water to a boil and cook elbow macaroni for 7-8 minutes until al dente. Reserve ½ cup pasta water and drain.

Melt 4 tablespoons of butter in a medium saucepan, whisk in ¼ cup of all-purpose flour, and stir continuously for 2-3 minutes.

Whisk in 2 cups of whole milk and 1 cup of heavy cream into the roux, cooking until the mixture thickens, about 5-7 minutes.

Stir in 1 teaspoon each of paprika, garlic powder, onion powder, and mustard powder along with salt and pepper. Simmer for 2-3 minutes.

Remove pot from heat and slowly add 2 cups of shredded sharp cheddar cheese and 1 cup of shredded mozzarella, stirring until smooth.

Mix the cooked elbow macaroni into the cheese sauce until fully coated, adding reserved pasta water to reach desired consistency.

Pour the mixture into the greased casserole dish and top with remaining cheese. Bake for 15 minutes.

Switch oven to broil and cook for an additional 2-3 minutes for a golden crust. Keep a close watch to prevent burning.

Let the dish rest for 5-10 minutes before serving.