Our recommendation of this 1897 cafe comes with a couple of caveats: we don't recommend paying for table service or eating anything other than the Sicilian-style sweet pastries that the place is known for. If you pay at the register for a coffee (good) and pastry (even better) and enjoy them standing at the bar, you should be happy.
Caffè e Pasticceria U. Giuliani
Monti, Esquilino & San Lorenzo