Boil the coconut milk. Let it cool. Thinly grease the molds with cooking oil. Make some pandan juice and pandan leaf cuts from fresh pandan leaves. I prefer using real pandan juice instead of the artificial pandan essence since the cupcake's pandan aroma would be very different with real pandan juice. Mix sugar and eggs together in high speed until the mixture is thick. Add in the sponge cake stabilizer. Mix well again until white and fluffy. By using spatula, add in flour, cold coconut milk, pandan juice and green coloring into the cake batter. Mix well slowly until even. Put a layer of fresh grated coconut on the bottom of the greased molds. Press the grated coconut a bit with one finger to make the final results firmer. Heat the steamer. Pour the cake batter onto molds until they're 90% full. Put one cut of pandan leaf on top to give extra pandan savor. Steam the cupcake for about 15-20 minutes. Release the cupcake from the molds and serve warm.