Beat egg whites into snow and add vanilla sugar and grated lemon zest with a pinch of salt. Gradually add the sifted sugar and stir in. Then stir the egg yolks into the batter.
Mix flour and baking powder and fold in sifted. Mix in the apples.
Grease and flour a bundt pan.
Pour in the dough and bake in the preheated oven at 180 ° C top / bottom heat for approx. 40 - 45 minutes.