Preheat oven at 370F.
Mix baking powder and flour together in a separate bowl.
Use a different bowl to beat egg whites on high until they become stiff and form a peak. Put aside.
In a large mixing bowl, beat the egg yolks slowly, and then add in the sugar and vanilla sugar.
When sugar is all dissolved, add the oil in to the mixture slowly.
Next, add in the yogurt and combine.
Add the flour and baking powder mixture to the wet mixture and combine.
Needs to look like a pancake batter mixture in texture.
Fold in the egg whites using a wooden spoon.
Add red currants to mixture and stir just until combined.
Place into a greased baking pan 9x12.
Bake 27-30 minutes on 370F. Check if ready by inserting toothpick inside. If clean, cake is ready.