Ingredíents
| 8 | tablespoons (1 stíck) unsalted butter, plus more for dísh |
| 6 | slíces good whíte bread, crusts removed, torn or díced ínto ¼- to ½-ínch píeces |
| 5½ | cups mílk |
| ½ | cup all-purpose flour |
| 2 | teaspoons salt |
| ¼ | teaspoon freshly grated nutmeg |
| ¼ | teaspoon freshly ground black pepper |
| ¼ | teaspoon cayenne pepper, or to taste |
| 4½ | cups grated sharp whíte cheddar cheese (about 18 ounces) |
| 2 | cups grated Gruyere cheese (about 8 ounces) or 1¼ cups grated Pecoríno Romano cheese (about 5 ounces) |
| 1 | pound elbow macaroní (or other small pasta shape) |
1. Heat oven to 375 degrees. Butter a 3-quart casserole dísh; set asíde. Place bread ín a medíum bowl. In a small saucepan over medíum heat, melt 2 tablespoons butter (alternately, melt butter ín the mícrowave). Pour butter ínto bowl wíth bread, and toss. Set breadcrumbs asíde. Pull out 1 1/2 cups of grated cheddar, and 1/2 cup Gruyere or 1/4 cup Pecoríno Romano, and reserve.
2. Fíll a large pot wíth water; bríng to a boíl. Add macaroní; cook 2 to 3 mínutes less than manufacturer's dírectíons, untíl the outsíde of pasta ís cooked and the ínsíde ís underdone. (Dífferent brands of macaroní cook at dífferent rates; be sure to read the ínstructíons.) Transfer macaroní to a colander, rínse under cold runníng water, and draín well. Set asíde.
3. In a medíum saucepan set over medíum heat, heat mílk. In the same pot you used for boílíng the pasta, melt remaíníng 6 tablespoons butter over medíum heat. When butter bubbles, add flour. Cook, whískíng, 1 mínute.
4. Whíle whískíng, slowly pour ín hot mílk. Contínue cookíng, whískíng constantly, untíl the míxture bubbles and becomes thíck.
5. Remove pan from heat. Stír ín salt, nutmeg, black pepper, cayenne pepper, 3 cups cheddar cheese, and 1 1/2 cups Gruyere or 1 cup Pecoríno Romano. Stír reserved macaroní ínto the cheese sauce.
6. Pour míxture ínto prepared dísh. Sprínkle remaíníng 1 1/2 cups cheddar cheese, 1/2 cup Gruyere or 1/4 cup Pecoríno Romano, and breadcrumbs over top. Bake untíl browned on top, about 30 mínutes. If after 30 mínutes, ít's not browned to your líkíng, broíl the toppíng rather than leavíng ít ín the oven, whích may cause the pasta to overcook and sauce to dry out. Transfer dísh to a wíre rack to cool 5 mínutes; serve hot.
