I love old-fashioned pasta tubes in a rich cheesy sauce, and this version, made with fontina cheese, is my favorite. While commercial macaroni and cheese has gotten quite the bad reputation as a convenience food, this Roman rendition will bring the childhood favorite back to your heart with its delicious, satisfying personality. The evaporated milk and egg replace flour as the thickening agent that binds together the oven-baked version. Do not attempt this without the canned milk (you can use skim if you like), as it stabilizes the sauce and prevents it from curdling, which all fresh-milk sauces do in the slow cooker environment. For a special touch, you can sauté some fresh bread crumbs in butter or olive oil and sprinkle them over the top before serving. Serve this with a tossed green salad with tangy vinaigrette and Chianti for a glorious little feast.