1. Prepare the moulds by placing the softened butter in a bowl and cream the butter using a hand mixer till it turns light and yellow. Use this to brush the moulds. Make sure you brush the moulds well, then set aside.

2. Combine the cake flour, sugar and baking powder in a bowl, sift it well at least three times. Set aside.

3. In a separate mixing bowl, combine egg yolks, water and melted butter and mix it well using a paddle attachment for 1 minute till well blended.

4. Gradually add the dry ingredients and continue mixing for 3 minutes until all ingredients are blended. Scrape the bottom and the sides of the bowl. Set aside.

5. In a separate mixing bowl, combine the egg whites and cream of tartar. Beat the egg whites using a whip attachment on high speed. Add the sugar gradually and continue to beat till you reach medium peaks or till the egg whites have doubled in size. Reduce the speed to low and run for a few seconds to eliminate air bubbles in the meringue,

6. Gently fold-in the egg whites into the batter using the cut and fold method. Make sure to fold-in gently to prevent the meringue from collapsing. Fold-in till eventually mixed.

7. Pour the batter into the prepared moulds and bake for 15 to 18 minutes in a pre-heated oven.

8. Once cooked, remove from the mould immediately and transfer it into the wire rack.

9. Brush with butter and sprinkle sugar (optional) and grated cheese. Enjoy!