The singapore Sling was invented at the famous Raffles Hotel by Ngiam Tong Boon. This recipe is my favourite mix, which I got from the Savoy Recipe Book, printed in the 1930's. The are many other recipes for Singapore Sling, which many can be found on the web.
Prep: 30 minutes
Cook: 30 minutes
Prep: 10 minutes plus 1 month to develop (minimum 1 week)
Prep: 20 minutes
Cook: 40 minutes