Even though there was some negative remarks about it here recently, La Tartaruga in the Ghetto was by far my most memorable meal...mainly for the pasta dishes. It would be the place I'd head to first if/when I return.

Agree with Leely2 about Checchino dal 1887 too. We concentrated our lunch on the "fifth quarter" items and were really pleased. I loved the atmosphere of the place too.

Don't know if these places are still there, it being now 5 years ago, but:

Best dinner: at L'Antica Enoteca, at via della Croce 76/8, at the corner of Vicolo dei Lupo. It looked more like a bar with a restaurant attached. We sat outside and had one of the best and one of the cheapest dinners during our stay in Rome. My husband spent the rest of the trip trying to find Ravioli in mushroom sauce that equaled his dinner there, without success. We were equally impressed with the big blue bottle of Aqua Salus, a simple natural water in a beautiful blue bottle with a cobalt blue cap (but then, we tend to be impressed by a lot of simple things).

Not the best, but we had lunch at Miscellana -- a student bar and restaurant on Via delle Paste off Via dei Seminario. Mostly Italian students, some off the beat tourists, who probably noticed the beer-inscribed patio umbrellas. Decent unpretentious food and a good salad.

trattoriatritone.com It's a little on the expensive side, but worth it.

http://www.trattoriatritone.com/english.html
This like might work. It's Antica Trattoria Tritone

Tuscan, I think you mean the onion flan, and it was NOT on the menu when we were there. Bummer. They did have two other types of flan, though.

Thin