Beat the butter, egg yolks and sugar until frothy. Mix the flour, baking powder, vanilla sugar and cinnamon well, add to the egg mixture and knead well.
Drizzle the quince and apples with lime juice and fold in with the nuts. Beat the egg whites until stiff and fold in.
Spread the mixture on a greased baking sheet. Bake at 180 ° C (top / bottom heat) for 35 - 40 minutes.