Baked Ziti with Prosciutto

"This adult version of mac ‘n’ cheese is sure to be a big potluck hit. It was given to us by Hugo Matheson, chef at the fantastic Boulder, Colorado, restaurant The Kitchen. Don’t skimp on the ingredient quality here—with so few elements, premium cheese and ham are paramount. What to buy: If you don’t have prosciutto, any thinly sliced, high-quality salt-cured ham such as jamón serrano will do. Or make it vegetarian by leaving out the prosciutto altogether. Be sure to use a good-quality cheese for this recipe. Please don’t buy the pre-grated kind, as it will not really give much in terms of flavor. If you don’t like Gruyère, an aged cheddar is a good substitute. Game plan: This whole dish can be assembled ahead of time and stored in the refrigerator for up to a day. To finish, take the dish out of the fridge, allow to sit at room temperature for 30 minutes, and then bake until heated through. This recipe was featured as part of our Modern Potluck menu...."