About a 20-minute walk from St. Peter's Basilica, this tiny trattoria is well worth the stroll. Also known as "Cacio e Pepe," Da Gianni turns out exclusively Roman food of high quality. Although there are no antipasti on offer, heaping plates of tonnarelli cacio e pepe (long pasta with sheep's cheese and pepper), tonnarelli alla carbonara, polpettone, and fried anchovies are simple and satisfying main courses. Sit outside at folding wooden tables and check out the area's film and television crowd as they talk on their cell phones.