Boil the macaroni in well-salted water until al dente. Drain and set aside.
Melt butter in a large pot over medium heat.
Whisk in the flour and cook, stirring, until lightly blond, about 1 minute.
Slowly stream in the milk and cream, whisking until smooth and slightly thickened.
Lower heat. Stir in cheddar, Monterey Jack, American, and cream cheese until melted.
Season with Dijon, garlic powder, paprika, salt, and pepper. Adjust to taste.
Fold in the cooked macaroni until evenly coated. Splash in milk if too thick.
Let rest two minutes to set. Garnish with parsley and serve warm.