At the end of the main street running along Lake Como, you'll find the Grand Hotel Villa Serbelloni in Bellagio. Enter prior to the main gate to access the lower restaurant (LaGoletta). Sit outside, which offers a great view of the pool, Lake Como, and the mountains beyond.
The service is by and far the best I've experienced in Italy, and the food was amazing. If you love fish, go with the La Trota Salmonata allo Spiedo. Actually, everything is first rate - from the pizzas, to the pastas and salads.
This review is the subjective opinion of a TripAdvisor member and not of TripAdvisor LLC.