ACTIVE TIME 40 MINUTES • TOTAL TIME 40 MINUTES
SERVES 8
6 tablespoons unsalted butter
1 cup fresh breadcrumbs
¼ cup grated Parmigiano-Reggiano cheese (1 ounce)
1 small yellow onion, finely chopped
½ cup all-purpose flour
6 cups milk, preferably 2 percent
¾ pound elbow macaroni
3 cups grated sharp white cheddar cheese (9 ounces)
1 cup grated Gruyère cheese (3 ounces)
1 teaspoon Dijon mustard
Coarse salt and freshly ground pepper
1. Heat broiler. In a large, heavy ovenproof skillet, melt butter over medium-high heat. Remove 1 tablespoon butter, and combine with breadcrumbs and Parmigiano-Reggiano in a bowl.
2. Add onion to skillet, and cook until softened, 4 minutes. Whisk in flour; cook, stirring, 1 minute. Whisk in milk gradually; bring to a simmer. Add macaroni and cook, stirring constantly and scraping bottom of pan, until tender, about 6 minutes. Remove from heat, stir in cheddar, Gruyère, and mustard; season with salt and pepper. Top with breadcrumb mixture. Broil until golden brown, 1 to 2 minutes.