Cook the pudding according to the instructions and let it cool down.
Beat margarine, sugar, vanilla sugar, salt and eggs until frothy, possibly with the hand blender.
Mix the flour and baking powder and sift over the mixture. Stir everything until smooth.
Pour the dough into the greased pan and press the edge up about 2cm (with floured hands - the dough is very sticky).
Peel the apples, remove the stones and cut into wedges. Mix the poppy seeds and pudding together and spread over the dough. Layer the apple wedges on top of the pudding poppy seed mixture.
Knead the streusel and spread over it and then bake in the oven preheated to 180 ° C for 50 minutes.