For a Vegan, a little paradise. My wife and I stayed at the Hotel Kolbe, just up the street from this country market. I ate my first meal in Rome in a courtyard in the back. Faro with Pomadoro, Simple and delicious. Probably the cheapest too.
The market had a great variety of local produce, meats, and flowers. If it was open during the week, I would have lunched there every day.
Walking distance from the Colleseum or the Palantine Hill.