Add sugar, vanilla sugar and egg in a mixing bowl and mix it well.
If possible with a hand mixer.
2)Mix together flour and baking powder and add to the mixing bowl. Mix it well. Now slowly add buttermilk into it.
Preheat the oven at 200ª celsius.
Spread a butter paper in the baking tray(the big tray used in oven) and pour the mixture into it. Now mix together grated coconut and sugar and spread over the mixture uniformly.
Bake the cake in the middle level of the oven for 25-30 mins. If the grated coconut is getting more golden brown in color, keep a aluminium foil over the cake and bake it. After 25 mins, insert a tooth pick into the cake for a min and see whether any particles sticks on it. If not completely cooked keep it for another 5-10 mins and check it in short intervals.
6)Mean while, pour the whipped cream in a vessel and add the butter into it. Stir uniformly and bring it to boil.
When the cake is completely cooked, take the tray out and pour this butter-cream over the cake uniformly.
The coconut cake tastes better directly after baking.