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

In the same pot, melt the butter over medium heat. Stir in the flour and cook for 1-2 minutes until golden.

Gradually whisk in the milk, stirring constantly until the mixture thickens.

Remove from heat and stir in the cheddar and mozzarella cheeses until melted and smooth. Season with salt, pepper, and paprika.

Add the cooked macaroni to the cheese sauce and stir until well combined.

Transfer to a baking dish and top with your choice of toppings. Bake at 350°F (175°C) for 15-20 minutes until bubbly and golden.

Serve hot and let guests customize their mac and cheese with additional toppings.