4 tablespoon unsalted butter
1 bunch leek greens, thinly sliced (from 1 1/2 pounds of leeks)
Salt and pepper to taste
3 tablespoons all-purpose flour
3 cups half-and-half or whole milk
2 1/2 cups Manchego cheese, shredded
1 pound elbow macaroni
Preheat oven to 350 degrees F. Melt 2 tablespoon of butter in large skillet. Add leeks and cook over high heat, stirring just until slightly wilted, 5 minutes; season with salt and pepper. Cook over low heat until very tender, about 20 minutes.
Meanwhile, in large saucepan, melt 3 tablespoons butter. Add flour and cook over moderately high heat, whisking, for 2 minutes. Add milk and bring to a boil, whisking until thickened, about 5 minutes. Remove from heat. Add 2 cups of cheese, season to taste and whisk until melted into sauce.
Cook macaroni according to package directions just until al dente. Drain well and add macaroni and cheese sauce to leek greens. Mix well.
Transfer to an 8 x 11-inch baking dish and top with remaining cheese. Bake about 40 minutes until bubbly. Brown under broiler for about 3 minutes. Let stand 15 minutes before serving.
From “Food & Wine,” November 2008.