Mix rice flour with 60g of water into a smooth paste in a heat resistant mixing bowl. Set aside.
Boil 100g water with 45g fine sugar and pandan leaf, till the sugar dissolves.
Pour the hot pandan-syrup from Step 2 into the rice paste in Step 1. Stir to mix well.
Transfer the bowl to a water bath and heat over low temperature. Stir regularly to prevent the rice paste from forming lumps at the base of the bowl.
When rice paste started to form lumps, remove the mixture from the heat.
Continue to stir till all the lumps disappear. The rice batter should be smooth and slightly thickened. Cover the rice batter partially, and allow it to cool down below 35°C
While waiting for the rice batter to cool down, activate the yeast by sprinkling the instant dry yeast over 1 tsp of water. Need not stir the mixture. Let it stands for about 30 minutes, or till frothy,
When the rice batter has cooled down to below 35°C, stir in the yeast mixture from Step 5
Cover and let it ferment at room temperature for about 150 to 180 minutes, or till you can smell a nice alcohol aroma. The rice batter will be filled with air bubbles at the end of the fermentation.
Start to heat up a steamer. Pour the batter into two molds coated with a thin layer of vegetable oil. Mix about 1/2 tsp of mild flavor vegetable oil to the rice batter.
Steam for about 15 minutes, off the power, and let the cakes stand in the steamer for another 5 minutes.