The Les Amis Group in Singapore have numerous restaurants, most of them highly recommended.
http://www.lesamis.com.sg/webtop/index1.html
Les Amis and Au Jardin are supposedly very good; Aoki is some of the finest Japanese cuisine outside of Tokyo I have ever had.
The Tung Lok Group have a number of Chinese restaurants which are supposed to be very good as well:
http://www.tunglok.com/restaurants
If you are staying at the Four Seasons, consult with Edmund Tan, the Chef Concierge -- he and his team are very much in the know of these sorts of things.
Enjoy!!