Pre-heat the oven to 160C (320F). (note 2)
Grease the bottom and the side of the cake pan with butter (not in ingredients) and line the bottom with baking paper (note 3).
If the cake pan has a loose bottom, cover the bottom and side of the cake pan with large aluminium foil (or a disposable round aluminium tray) so that the foil continuously covers the bottom and the side to just below the rim.
Add cream cheese in a bowl and whisk over water bath (not too hot) to soften the cream cheese. Add butter and whisk until the mixture becomes creamy with no lumps.
Remove the bowl from the water bath and add the remaining Batter ingredients one by one in the order of the ingredients list. Mix every time an ingredient is added. Mix well until the color of the batter becomes consistent.
In a new bowl, add egg whites and beat until they become foamy.
Add sugar in 3-4 batches while beating the egg whites fast. Beat until soft peaks form (note 4).
Add a third of the meringue to the batter and fold gently using a spatula until white meringue mixes into the batter.
Now transfer the batter to the meringue bowl and fold gently until the trace of the white meringue disappears.
Pour the batter into the cake pan. Drop the pan from 10cm (4") high few times to remove air bubbles.