1 package (16 ounces) uncooked Fusilli pasta
1/2 cup (1 stick) plus 1 tablespoon unsalted butter, cubed and divided
1/2 cup all-purpose flour
4 cups (1 quart) whole milk
1 tablespoon kosher salt
6 ounces Cheddar cheese, shredded (1 1/2 cups)
6 ounces Havarti cheese, shredded (1 1/2 cups)
3 ounces Asiago cheese, shredded (1 cup)
Pepper to taste
1/2 cup Panko bread crumbs
Fresh rosemary leaves, optional
1 Heat oven 400°F. Cook pasta according to package directions until al dente; drain.
2 Meanwhile, melt 1/2 cup butter in a Dutch oven over medium-low heat.
3 Whisk in flour until light brown. Gradually whisk in milk and salt.
4 Bring to a boil; cook and whisk for 2 minutes or until thickened.
5 Reduce heat to low; gradually whisk in the cheddar, havarti and asiago until smooth.
6 Stir in pasta. Remove from the heat. Season with pepper to taste.
7 Spoon pasta mixture in a greased 13 x 9-inch baking dish.
8 Melt remaining butter; toss with bread crumbs.
9 Sprinkle crumb mixture and rosemary if desired over top.
10 Bake for 25-30 minutes or until topping is golden brown.