Basic sponge cake

Variation from this recipe . The result is very fluffy sponge cake!

Ingredients
4 eggs, separated
4 tbsp sugar, combine with a bit of vanilla sugar
4 tbsp flour
1 tsp baking powder
pince of salt

Fillings
Hazelnut cream spread (example nutella)

Method
1) Pre-heat oven at gas mark 3.
2) Beat egg whites with a pinch of salt. Beat until stiff. Set aside
3) Beat egg yolks with sugar (including vanilla sugar) until creammy. Combine flour and baking powder into egg yolks -sugar mixture and mix well. Next, fold in the egg white (beaten earlier) carefully into the until well integrated.
4) Pour cake batter into lined baking tin and bake for 15 mins.
5) Spread hazelnut cream spread or any other fillings you like when cake is completely cooled.