Cream the butter. Stir in pudding, a spoonful at a time. Cut cake twice [horizontally]. Fill with the buttercream, and also spread buttercream on top. ((Note: Baking powder and for that matter, vanilla sugar is sold in small packages in Germany. The average cake uses one package. K.B.)) ((*Note: Probably a package of pudding mix, as the later instructions refer to pudding. K.B.))