This is a simple application of a basic cheese sauce. I don't think it's based on any recipe in particular, although it's probably inspired by the macaroni-and-cheese cookbook that I picked up a year or two ago.
|1 lb||pasta, cooked 1–2 minutes short|
|2 cups||hot milk|
|8 oz||good cheese, shredded|
|1 oz + 1 tsp||butter|
|1||leek, cleaned and chopped|
To prepare asparagus: Heat oven to 400°F. Season asparagus and toss in vegetable oil. Roast asparagus on a wire rack over a sheet pan for 8–10 minutes, until tender. Chop roasted asparagus in 3/4-inch pieces. Reduce oven to 375°F.
To make cheese sauce: Melt 1 oz butter in saucepan. Cook chopped leek, covered, stirring regularly, until soft and transparent. Add 1 tsp butter and then 1 oz flour. Stir until a roux is formed and let cook over medium heat for 1–2 minutes. Add hot milk, whisking rapidly, until fully incorporated. Simmer until thickened, then add cheese and 1/8 tsp freshly grated nutmeg. Stir until completely mixed, then stir in chopped asparagus.
Put cooked pasta into a 9×13 casserole and mix sauce into pasta. Bake for 20 minutes.