Line the baking tin with baking parchment - crosswise.
Peel & trim the apples - cut them into thin slices (1-2 mm). Set aside.
Preheat the oven to 160° C fan.
Mix white sugar, vanilla sugar, salt & spice mix.
Mix flour & baking powder.
Mix butter and sugar mix with the handheld electric mixer until creamy.
Add the eggs and mix ...
Add the whipping cream ... & mix.
Add the flour mix & mix.
Fold the apple slices into the cake batter & pour into the baking tin.
Sprinkle the brown sugar on top (optional).
Bake in the preheated oven at 160° C fan for 40 min. Let it rest for another 5 min w/o heat & fan.
Let the cake cool down.
Mix icing sugar & spice mix. Add whipping cream & vanilla extract. Mix with a spoon. Sieve if necessary to eliminate sugar lumps.
Add icing on top of the cake - as much as you like.