Soak the rice overnight, and then drain completely. Make sure no water remains in the rice, and you can do this by leaving it in a sieve to drain for as long as you can.
Please click HERE for step by step instructions on making the perfect mini vitumbuas.
Put the rice, coconut milk, yeast and cardamom powder into your blender and blend until completely smooth. This may take a while but stick to it. Keep blending for a full minute at a time, giving the blender a rest of a few seconds between pulses. Once you're satisfied that the rice has been mashed completely and your batter is smooth, pour it out into a bowl, cover and set aside to rise for 30-60mins.
Once risen, add the sugar and mix it in using your hand. Make sure the sugar is completely mixed into the batter.
Now put some oil in your Appam pan or any tiny karai and heat it up. Then add batter using a spoon into your pan and fry the vitumbua, first on one side and then turn it over to do the other side until golden on both sides.
Serve warm! :)