Dear Hui -

In this country, about the only way to buy buttermilk is by the quart, and then most people don't use it for anything but baking - so a lot of times it just gets wasted. I've seen powdered buttermilk that you just reconstitute with water, but the easiest way is to add about a tsp or little more to a cup of milk - I usually do this first, then mix up the dry ingredients and let is sit while I do that - grease the pans, etc. - then by the time I want to use the milk, it has soured and even thickened a little.

Hope this helps you out! How about sharing some baking recipes from Singapore - anything different?? Do you use metric measurements or cups/tsp, etc.

I haven't ever figured out the conversions for grams, etc. of dry ingred.