Hazelnut Gugelhupf

Any nuts may be used for this, though the hazelnut version is the classic Viennese one. It adds flavor to finish this cake with a nut oil, such as the hazelnut oil used here (walnut and almond oils are also available in specialty stores). If you have trouble finding these oils, use the equivalent amount of melted, clarified butter (melted butter that has had all the foam and liquid removed).