Cook macaroni (pasta) according to the packaging instructions.
Shred the hard cheese(s).
Cook milk with butter and flour.
Add all types of cheese one by one and stir until combined well. When adding cheese, remove the pot from the stovetop and mix it nicely, then put it back on the stovetop. The sauce is done when it looks stringy.
Pour the cheese sauce in a baking pan together with macaroni.
Fry the breadcrumbs with bacon or prosciutto at high heat and top the macaroni and cheese with them.
Bake mac and cheese for about 30 minutes at 175 degrees Celsius.