Step 1

Bring a large pot of salted water to boil and cook macaroni for 1-2 minutes less than instructed on packaging. There should still be a bit of bite to the pasta. Rinse with cold water, then drain and set aside.

Step 2

Preheat oven to 375º F and lightly grease a 9x13-inch baking dish with butter or non-stick spray. Toss bread cubes with 2 tablespoons melted butter in a medium bowl and set aside.

Step 3

In a large saucepan over medium heat melt remaining butter (6 tablespoons) until bubbly, then stir in flour. Cook, stirring frequently, for 1 minute.

Step 4

While whisking, pour in warmed milk until fully incorporated. Continue whisking until mixture thickens and bubbles up.

Step 5

Remove from heat and season with salt, pepper, nutmeg and cayenne, then stir in 3 cups cheddar cheese and 1 1/2 cups gruyere.

Step 6

Stir drained pasta into cheese sauce, then transfer to greased baking dish. Top with remaining cheddar and gruyere cheese, then sprinkle buttered breadcrumbs on top.

Step 7

Place in oven and bake for 25-30 minutes, or until golden brown on top.

Step 8

Remove from oven and serve hot!