We spent 4 days on the Riviera di Levante, based in Sestri Levante. Driving down from Piemonte, we stopped for lunch at La Cucina di Nonna Nina in San Rocco just south of Camogli. The simply grilled fish was perfectly prepared and delicious, as were theantipasti and primi. Prices were very reasonable.
Logistical hint: Approached from Camogli, it's simple to drive to Nonna Nina and to park on the street in front of the restaurant, as opposed to coming from the south which, as other posters have pointed out, can only be done on foot and via long flights of outdoor stairs.
Sestri Levante was a good base. The town is not tiny, but still is peaceful and attractive although without "historical" or architectural interest. Despite being a beach resort, the town does not have a "touristy" feel (at least not in early October). It sits at the base of a small peninsula dividing two bays, and the waterfront promenade along the larger one is pleasant. We stayed at the very fine Hotel Helvetia overlooking the smaller bay and its modest beach, called Baia di Silenzio (strongly recommended).
In season (through August or possibly September), there are boats from Sestri east to the Cinque Terre and west to Portofino. Even in October, however, the Cinque Terre still are served by boats from the westernmost of the 5 towns (Monterosso) and there are boats to Portofino (and San Fruttuoso) from Rapallo, both of which starting points are only 15-20 minutes from Sestri by very frequent local train along the coast.
On our four evenings in Sestri, we had dinner at three different restaurants. All were walking distance from the Helvetia, and the after-dinner walks back through the quiet streets along the water were quite pleasant. (Barbarinibee, if you're reading this, we had tried octopus for the first time at a restaurant earlier in the trip, at no less than Villa Crespi in Orta San Giulio, and on that basis decided to skip Mario Polpo and its related polpo establishments in Sestri. Sorry.) The restaurants we did try were as follows:
A light meal at La Calanca (following lunch at Nonna Nina) was OK but not noteworthy. The Portobello, facing the Baia di Silenzio, was very good. The highlight for us was El Pescador, facing the larger bay, which despite the Spanish name is as Italian as it gets.
The true gamberi rossi, grilled, were what drew us back to El Pescador a second time. But the pesce alla Ligure (that night a dorade, oven-baked with potatoes) also was excellent, and on our second visit a simply grilled dorade was outstanding. The antipasti and primi also were first-rate. El Pescador also, again despite the name, has a large selection of meat dishes, and grilled meats are cooked over charred logs in a large woodburning fireplace at one end of the front dining room.
So, thanks to all who recommended Nonna Nina, and we hope our comments on Portobello and El Pescador will be useful to future Sestri Levante visitors.