1. Bring a large pot of salted water to a boil. Cook elbow macaroni until al dente (7–8 minutes), drain, and set aside.

2. In a large saucepan or deep skillet, melt the butter over medium heat. Whisk in the flour and cook for 1–2 minutes to make a roux.

3. Gradually pour in the milk and heavy cream while whisking constantly. Cook for 4–5 minutes until thickened.

4. Lower the heat and stir in the shredded cheddar, mozzarella, and Gruyère cheeses a handful at a time. Stir until smooth and creamy.

5. Season the sauce with salt, pepper, ground mustard or Dijon (if using), and paprika or cayenne (if desired).

6. Add the cooked macaroni to the sauce and stir to coat evenly.

7. Serve immediately for stovetop version, or transfer to a buttered baking dish. Top with extra cheese or breadcrumbs and bake at 375°F for 20 minutes until golden and bubbly.