Melt chocolate with about two T of water.
Let cool while you are creaming butter and sugar.
Cream (fluff) the sweet butter, add gradually the well sifted powdered sugar, add a yolk at a time and cream well.
Add melted chocolate and beat to a fluff.
Add flavoring.
When cake is cool spread thick between layers and on top and sides. Cover all generously with ground nuts.
Filling must never have a sugary taste. To obtain a smooth filling use either less sugar or more yolks. Place cake in refrigerator to set. Keep in refrigerator when not in use, but give it a chance to soften up before serving so that filling will not be too hard.
Almond flavoring is delicious, but do not use too much as it makes the butter bitter.