How about a cooking class with 'at Sunrice' (yes, that's the name of the outfit).

It's not old-old (started up ten years ago), but has linked up with some decent heavyweight cooking schools. Also it's Singapore Government recognized so that gives locals some comfort that after they leave, they'll be able to find jobs in the industry.

A short course idea, go to
http://www.at-sunrice.com/corp/SpiceGardenWalk.aspx