Do you mean the Tiffin Room at Raffles?
But many other hotels here offer High Tea buffets too. For instance, the Rose Veranda at the Shangri-La is very popular for its range of teas, pastries, cakes and scones.
TWG is indeed a Singaporean brand, and is served on First and Business class on Singapore Airlines
Completely different from the UK Twinnings. TWG does have a mind-boggling array of teas, and I like visiting their outlet at Ion Orchard (although sometimes it makes me feel like a goldfish in a bowl).
If you are willing to splurge, check out the Cookie Museum at the Esplanade Mall, another Singaporean establishment that offers fresh-baked cookies paired with floral teas.
Here's a write-up by CNNGo for more information on popular high teas in Singapore:
http://www.cnngo.com/singapore/eat/city ... eas-184740