Basilico serves good Italian food. Portions are filling and the prices, I think are reasonable. The ambience is absolutely nice, and makes for a perfect choice for a lovely evening. It is located on Sukhumvit Soi 20.
You can also also visit Rang Mahal which is right opposite Basicilo. Like its name suggests, it serves Indian food. But, be aware that it is fine dining and adheres to a strict dress code. No sleeveless, no shorts, and some other dress code, which I cannot remember. The only thing I distinctly recall is the smile on our faces when we noticed our respective dresses and the contradictory dress code, which eliminated us automatically from the Rang Mahal junta!