Bring a large pot of salted water to a boil. Add the elbow macaroni and cook until al dente. Drain and set aside.

In a large saucepan, melt the butter over medium heat. Whisk in the flour and stir constantly until smooth and bubbling.

Gradually whisk in the milk and heavy cream. Stir constantly until the sauce thickens, about 5-7 minutes.

Lower the heat and stir in the cheddar and mozzarella cheeses until fully melted. Season with salt, pepper, and paprika if using.

Add the cooked macaroni to the cheese sauce and mix until fully coated.

Transfer to a greased baking dish, top with breadcrumbs and extra cheese if desired. Bake at 375°F for 15-20 minutes until bubbly and golden.