I actually ate here twice in two days, by happenstance: first, for lunch with just one other person, and the next day in a party of 11 for dinner.
The Osteria is conveniently located, not far from the Karen roundabout, in what was a private home at one time, and tables are spread out through the gardens, as well as on the terrace and indoors. The waitstaff is abundant and attentive.
The food is authentically Italian, but one can order from the menu as one wishes, without having to choose a primo piatto and then a secondo, etc. Shortly after one sits down, freshly baked pizza bianca topped with fresh, chopped tomatoes is brought to the table as a complimentary appetizer: a nice touch. For lunch the first day, I started with a classic appetizer: bresaola with arugula and shaved Parmesan. It was plentiful and fresh and served with olive oil and lemon wedges. My companion started with a classic caprese salad, which also was large and looked very good. We both decided to have the risotto ai funghi porcini for our main course. It was nicely flavored, but the rice didn't quite get tender enough, as if the chef had rushed the preparation. We ordered a bottle of water and we each had a large glass of the house red wine, which was probably the equivalent of 2-3 regular restaurant glasses of wine. We finished with espresso.
The next night, I was in a party of 11, and we had a nice table inside because the weather was a little cool and rainy. Everyone seemed to enjoy the food they ordered, and the waitstaff kept the wine and beer flowing. I ordered "penne all'arrabiata" which was plentiful and quite spicy, which I enjoy. The pasta was just slightly overlooked, according to my preference, but good nonetheless.
I picked up the tab for the evening, and 11 of us ate and drank for roughly $360 US. You would be hard-pressed to do that at a similar quality Italian restaurant in the States (or in Italy, for that matter.)
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