Step 1: Cook the Pasta

1. Preheat your oven to 375°F (190°C).
2. Bring a large pot of salted water to a boil. Add the macaroni and cook until just al dente, following the package instructions. Drain the pasta, rinse under cool water, and set aside. Toss the pasta with a tablespoon of butter or oil to prevent it from sticking.

Step 2: Make the Cheese Sauce

1. In a large saucepan, melt 4 tablespoons of butter over medium heat. Once melted, whisk in the flour to create a roux. Cook for 1–2 minutes, stirring constantly, to eliminate the raw flour taste.
2. Slowly pour in the milk and cream, whisking constantly to avoid lumps. Cook for 3–5 minutes, or until the mixture thickens and coats the back of a spoon.
3. Stir in the Dijon mustard, garlic powder, smoked paprika, salt, and pepper. Reduce the heat to low.
4. Gradually add the shredded cheddar, Gruyère, and Parmesan cheese, stirring until fully melted and smooth. Taste and adjust the seasoning as needed.

Step 3: Combine the Pasta and Sauce

1. Add the cooked pasta to the cheese sauce, stirring until every piece is evenly coated.
2. Transfer the mac and cheese mixture to a greased 9×13-inch baking dish, spreading it out in an even layer.

Step 4: Make the Breadcrumb Topping

1. In a small bowl, combine the panko breadcrumbs, melted butter, Parmesan cheese, and dried parsley (if using).
2. Sprinkle the breadcrumb mixture evenly over the top of the mac and cheese.

Step 5: Bake the Mac and Cheese

1. Place the dish in the preheated oven and bake for 20–25 minutes, or until the top is golden brown and crispy.
2. If desired, broil for the last 1–2 minutes to achieve an extra-crispy topping. Keep a close eye to prevent burning.

Step 6: Serve and Enjoy

Remove the baked mac and cheese from the oven and let it cool for 5–10 minutes before serving. Garnish with fresh parsley if desired, and serve warm as a main dish or side.