You will get varying opinions about Cinnamon Club. I'm originally from the U.S., not that it matters, and I found it a lovely place (great decor) and enjoyed the food. From what I remember (the meal was a few years ago), it seemed like 'designer' Indian food... not what one would get at more traditional places. I think that's why many poo poo this restaurant. I also have to confess that I didn't know much about Indian food at the time as I found it not a good choice in NYC.
You might enjoy Amaya, the weekend buffet at Bombay Brasserie or some other places more.. or Quilon, which is highly praised. Avoid Brick Lane!
41 Buckingham Gate, London, Greater London SW1E 6, GB
140 Courtfield Road, London SW7 4QH, GB
The Cinnamon Club
The Old Westminster Library, 30-32 Great Smith Street, London SW1P 3BU, GB