Beat butter until fluffy, then add the vanilla sugar. Taking turns, mix in sugar, eggs, almonds, breadcrumbs and a mixture of cornflour, baking powder and rum.
Transfer the mixture into a greased round springform cake tin.
Preheat oven to 180 C / Gas 4.
Place whole apples into the mixture and sprinkle with currants and almonds.
Bake in preheated oven for about 60 minutes. After baking, sprinkle with sugar. Release from the tin and let cool.
