Combine the tomatoes, basil, garlic, and a sprinkling of salt in a colander. Place in the sink or over a plate with a rim. Let stand at room temperature for about 1 hour.
In a large serving bowl, mix the ricotta, milk, pepper, and nutmeg with a wooden spoon until fluffy. Stir in the mozzarella and fontina. If not serving right away, cover with plastic wrap; lea