Mix the soft margarine, salt, egg and sugar together.
Now mix the flour with the baking powder, add and knead into a smooth dough.
Roll this onto the baking sheet (you can also use a springform pan), press it down firmly and poke it with a fork.
Using the milk, sugar and pudding powder, cook a pudding and let it cool.
Then stir in the sour cream and pour the mixture into the mold and distribute it evenly.
For the crumble, cement the flour, butter and sugar well and then distribute them roughly on the cake.
Bake in a preheated oven at 180 ° for about 30 minutes.