Take 2 filo sheets, smear them with melted butter and bake until lightly browned. Prepare the pudding with the milk and sugar according to package directions. Allow the cream to cool.
Whip the cream until fluffy and whip the butter with the powdered sugar. Spoon by spoon, add the pudding to the butter and stir. Finally, mix in the cream. Stick the filo pastry sheets together with the cream in a suitable form.
Leave the cake for a few hours in the refrigerator before you serve. Serve a slice of filo pastry, decorated with crushed walnuts and powdered sugar.