The pasta
1 lb elbow macaroni or cavatappi. Cook 2 minutes shy of al dente — it finishes baking in the oven.
The cheese
2 cups sharp cheddar, 1 cup Monterey Jack, 1/2 cup parmesan. Block cheese, not pre-shredded — the anti-caking agents on pre-shredded prevents it from melting properly.
The sauce
4 tablespoons butter, 4 tablespoons flour (cook 1 minute to make a roux). 3 cups whole milk, 1 cup half-and-half. 1 teaspoon salt, 1 teaspoon mustard powder, pinch of cayenne. Whisk in cheese off the heat.
Bake
Mix pasta with cheese sauce. Pour into a greased 9x13. Top with extra cheese and breadcrumbs. Bake 350°F for 30 minutes.