Preheat the oven to 200 ° C (fan oven 180 ° C, gas mark 3-4).
Wash, peel and core the apple, cut the flesh into small pieces. Sift the flour and baking powder. Mix with almonds and apple pieces. Beat the eggs until frothy. Mix with sugar, vanilla sugar, fat, milk and salt until smooth. Crumble the marzipan mass and stir in. Fold in the flour mixture.
Pour the batter into the mold. Bake the muffins for 15-20 minutes.