Carniolan pork sausages; laurel-marinated trout; Istrian salted cod with candied red peppers; dandelion-filled ravioli with aged Tolmin cheese and linseed cream; steamed walnut ice cream with kefir, pollen and spelt groats, paired with orange wine: Gostilna Na Gradu promises a fine exploration of Slovenian produce, perched in Ljubljana Castle over the country's lovely capital.