CAVEAT: I've only eaten here once, and only had one dish.
I stopped into Ecco while waiting to dry off from too much wine at a meeting. It was about 7:00pm on a Tuesday or Wednesday and the restaurant was about half full. I was seated within a few minutes of arrival and a few minutes after that had bread and a bottle of water in front of me.
I ordered the foie gras hors d'œuvre. The liver is served on brioche and topped with sprouts and onion, with a Sauterne reduction, which had an overpowering berry flavor to it. I scooched the sauce off to the side.
I love duck liver mi-cuit, and this was cooked just a tad more than mi-cuit. That said, most people won't notice as it wasn't over-done, just a little more done than I prefer. Someone on another site thought it was slightly underdone, so the chef probably found a good balance between extremes. It was still nice -- delicately flavored, smooth. I'd order it again.
The service was friendly and sufficient and the surroundings understated and comfortable. Ecco seems to be a nice place relax over dinner and a pleasant conversation.
Small technicality... since it's July, and the liver comes fresh from birds in Sonoma, I'd call it foie du canard and not foie gras du canard. However, the flavor was nice, it was just smaller and leaner than you'd get in winter.
This review is the subjective opinion of a TripAdvisor member and not of TripAdvisor LLC