1 lb casarecce, fusilli, or shell pasta
1/2 lb prosciutto, thinly sliced
1 quart whole milk or heavy cream, room temperature
1 1/2 C fontina or Gruyere cheese, grated, divided
1/2 C parmesan cheese, grated
1/2 C all-purpose flour
1/2 C (1 stick) unsalted butter
1 pinch freshly grated nutmeg
Kosher salt and freshly ground pepper, to taste
Preheat oven to 400 F degrees. Lightly grease a 9x13 baking dish.
Bring a large pot of salted water to boil. Cook pasta until al dente. Drain and set aside.
In a large saucepan, over medium heat, melt better. Sprinkle in flour and whisk mixture until smooth.
Continue to stir and slowly add milk or cream. Whisk until smooth and creamy.
Cook béchamel for 8-10 minutes, or until thickened.
Once thick, remove from heat and season with nutmeg, cheeses (reserve 1/2 C fontina), prosciutto, salt, and pepper.
Return pasta to pot and pour prosciutto and béchamel sauce over the top.
Stir until thoroughly coated.
Pour pasta into baking dish and top with remaining fontina.
Bake for 25-30 minutes, or until cheese is bubbly and golden brown.