Knead the crumble ingredients and chill. Cook the pudding with milk and sugar according to the instructions on the packet.
Mix the butter with sugar and vanilla sugar until frothy. Gradually add the eggs. Sift the flour and mix it with the baking powder and cornstarch. Gradually stir the flour mixture into the dough. Add milk.
Pour the dough into a greased tray or springform pan and bake for about 10 minutes at 175 ° C in a hot oven. Spread the pudding and poppy seeds unevenly on the bottom. Put the crumble on top. Put back in the oven and bake for 30-40 minutes.