Add thick coconut milk, vanilla essence and mix well again.
Pour custard mixture into each custard mould (3/4th of the mould) or flat bowl and cover this with aluminium foil or grease proof paper.
Steam in pressure cooker (without weight) or steamer for 30 - 35 minutes on a medium heat (or pour the custard mixture in a baking dish and bake at 150 degrees Centigrade or 300 degrees Fahrenheit for about 35 - 40 minutes or until the custard is set).
Remove from steamer and keep aside to cool for 15 - 20 minutes.
Unmould and serve warm or cool (place a plate on top of the custard bowl and carefully flip it upside down).