Mix together all the ingredients, excluding the butter and walnuts. The dough needs to be soft. Leave it to rise overnight.
Next, divide the dough into 24 equal parts, roll them out into sheets. Smear each sheet with butter.
Arrange 12 of them in an oiled tray, sprinkle with walnuts and place the other 12 on top.
Cut them into squares. Pour on melted butter. Bake in a moderate oven.