Trim the giblets, eliminating the green bile ducts from the livers. Rinse them for a good, long time, then dice. Soak the dried mushrooms for 20 minutes in at least two changes of warm water. Drain, rinse, and squeeze well, then cut them into small pieces. Peel, halve, and seed the tomatoes, then cut into small pieces.
Chop together finely the onion and the prosciutto fat and crush the