Small, local, excellent restaurants in Monti and Trastavere?

For breakfast you want a neighborhood coffee bar with a selection of cornetti (pastries). They are found throughout the city. Any place serving an American-style breakfast is going to be touristy and by definition not excellent. Da Enzo in Trastevere has a good reputation for lunch and dinner, however they do not take reservations so you must wait in line.

We had a great meal at Ristorante la Nuova Piazzetta a couple of months ago
https://goo.gl/maps/jXsJFodwPqUnUxPDA

I enjoyed lunch at Trattoria da Enzo al 29 back in 2015. I stumbled upon it and was lucky to get seated right away. An attempted repeat visit was unsuccessful; it's very popular. The location is Via dei Vascellari 29 in Trastevere. There's also a Ristorante da Enzo at Via Ennio Quirino Visconti 39-41 in Prati, which I suspect is under the same ownership but is fancier and more expensive. The Trattoria is a very simple-looking place but well respected. I believe it's a stop on some food tours, and I've read that it's a place chefs head for late-night dinners after their restaurants close. (I can't vouch for the accuracy of those statements.)

We enjoyed Ristorante Terme di Diocleziano at Via del Viminale 3. It's in walking distance of Monti, toward Termini station.

The clientele was mixed: tourists, to be sure, but also locals. The service was great, and the food traditional and very good. If you go more than once, the staff will remember you, and perhaps offer a special treat!

We stayed in Monti and enjoyed La Taverna dei fori imperiale, which was a short walk from our apartment, reservations required. You can look on Tripadvisor for reviews.

Yo MM,
Here is an excerpt from our lengthy TR from a few years ago. It is actually about Puglia, but its ending (seen below), is all about Monti.
Hope it helps.
ROME: THE FULL MONTI

Monti is a gentrified area in Rome with a hilly, village tone. It was known until recently as the wrong side of the tracks, home to hookers and thieves. Its ancient name was ‘Subura’ (‘outside the sacred center and its fire-wall’), hence our word ‘suburb’. Monti is a residential area, but it is also all about unique boutiques, whose products would make superb gifts. We can also attest to its abundance of very good restaurants. There are some real winners there.
We recommend friendly Monticiani, which is at 84 Panisperna. It is a casual caffe-bistro, more locals than tourists and features many Argentine items on its reasonably-priced menu. It is open from 7am and the service is friendly. It is our kind of unpretentious 'local' place, so we went more than once. (my wife: “Ladies, the tall owner is probably the most handsome man in Monti”).

Locals recommend a bar on v. Merulana called ‘Panella l’arte delle Pane’. It offers a wide variety of good food. Right around the corner on v. d. Statuto, there is a great cake shop. Self-caterers should know that there is a classic butcher, plus a good fish shop, in Monti.
Perennial fave bar, ‘Tre Scalini’ (three flies), seems always to be packed, so with my hearing issues, we gave it a pass. Once as we passed it on the street, we witnessed a patron cradling his tiny baby inside the bar. That was a first.
Other bars: Black Market, Libraria Caffe Bohemian and Analemma.

If you want to buy designer chocolate, then ‘Grezzo’ is a good choice, all modern and run by women. If you want rustic Calabrian deli foods, then 'Delizie di Calabria' on v. Serpenti is pretty good.

Places that we heard were good but ran out of time for:
L'Asino D'Oro, Carbonara, Urbana 47, Enoteca Cavour, Alvino, Fafiuche, la Caseta, Hasekura, Guru and Maharaj. The latter trio speak to Monti's multi-kulti component and are close to the fountain-piazza, Madonna di Monti, which serves as the ground zero/meeting place for Monti. It was at this fountain during a heat wave back in May, that some African refugee men caused controversy by stripping down to their civvies and cooling off by soaking inside the basin. Much Romanesco slang by local curmudgeons ensued. Film fans, note that Woody Allen and Alec Baldwin shot a memorable scene for ‘To Rome with Love’ just one block west on tiny v. Neofiti.

We saved the best for last:
Antico Forno Serpenti—top-quality bakery and they too, do a modest lunchtime buffet as well. Their pizza was the best that we tasted on this trip to Italy.

Which adjective best describes Monti? (circle answer)

Quirky, hip, funky, boho, cobbled, youthful, hilly, arty, bustling, trendy, gritty, twisty, vine-strewn.
A-all of the above

Who Knew? SPQR Historia: Julius Caesar was born in this neighbourhood, back when it was a tough, effluent-ridden, fire-prone slum. Juvenal wrote in his satires that the main cause of death in the noisy chaos of Subura/Monti was insomnia!

I am done. The end.

In Trastevere I have found myself wanting to move in at Carlo Menta for lunch and dinner. The food is honest, decent size servings, wonderful service and very affordable.

Carlo Menta in Trastevere gets my vote too.

Always a fan of Dar Poeta in Trastevere. Pizza is legendary but roasted vegetables a wonder.

Close by, near Campo de' Fiori, are Elle Effe (Sicilian) and then Ristorante Emma, which is owned by the Roscioli family of salumeria and Forno bakery fame.