Roman Ricotta Cheese Crostata with Cherries or Chocolate

When in Rome, do as the Romans do: head straight to the tiny nondescript Pasticceria Boccione (also known as the Burnt Bakery or the Jewish bakery) in the ghetto ebraico (Jewish Ghetto) near the Tiber. There, four sisters make the same slightly burnt baked goods until they run out each day. Whether composed of tourists or locals, there is always a line outside. One of the popular staples is a rich ricotta cake wrapped in a crostata crust, called Cassola, a Christmas must in Rome. Acc