“Why the fuck am I here?” Self-taught Slovenian chef Ana Ros recalls asking herself this question when she attended gastronomy’s great gathering of the clans, Cook It Raw, in Poland in 2012. She was the only woman present, and felt that her invitation owed more to tokenism than to any profound engagement with what she was doing at her restaurant, Hisa Franko in the Julian Alps.

Five years later, Ros was named the best female chef in the world and Hisa Franko firmly established in the world’s top 50 restaurants. Whatever one thinks of such lists — and we don’t love the patronising qualifier, either — Hisa Franko more than deserves its slew of accolades, most recently the award of two Michelin stars, making it the first Slovenian restaurant to achieve the feat.

Something of a celebrity in her own country, Ros is forthright, passionate and utterly rigorous in her approach to food, yet equally lacking in swagger and pretension. The concept of terroir, by which location becomes a distinguishing factor in the character of produce is familiar when applied to wine, less so, nowadays, to people, but in the ancient world the impact of climatic variation, seasonal variations and landscape itself was a familiar determinant of human evolution. In Airs, Waters, Places, Hippocrates suggests that people living in mountainous regions are more likely to possess endurance and courage, with a tendency to “wildness and ferocity”.

Renaissance writers applied similar distinctions to food: thus Fynes Moryson, an English traveller of the sixteenth century, equated the rather austere, sober character of Florence’s architecture with its cookery — “spare diet but wonderful cleanliness” being his verdict.

The correlation of physical landscape, ingredients and personality is as immediately obvious in the Soca valley, where Hisa Franko is located, as in Ros and her food. “In my eyes,” she explains, “the kitchen is a symbiosis of three elements: the territory, the season and the personality of the chef.”

As the road climbs across the Italian border from the fell outlands of Udine to the flower meadows and bright rivers of Slovenia, it’s hard not to feel one is travelling back in time. The greens are suddenly greener, the cherries plumper, the goats goatier. The valley flattens out between vertically-forested slopes, with a sudden, breathtaking glimpse of a conclave of marble-mitred mountains.

A long, low, faded-pink building set between two streams, Hisa Franko has a haphazard, unmanicured charm: here a cow peers incuriously between a tangle of wild white roses, there an old cart makes a bench next to a modern chair under a vined terrace. There’s a relaxed wine bar and a few simple, comfortable rooms for guests who want to stay overnight, but the atmosphere changes gear in the restaurant proper.

Ros describes her conception of the progress of a meal as symphonic, layering counterpoints of flavours within a cycle which contrasts, repeats and unites. The menu is divided into three sections: “Finger Bites”, “Fork Bites” and “Sweet Conversions”.

The first service was an apricot tartlet with carrot and blue cheese, a little sunburst of sweet and sharp, a tiny cured sardine with black lemon and a delicate taco of plantago (less elegantly known as fleawort) with wild herbs.

Each fairy-sized portion was a tiny jewel, but the wit and lightness of their presentation belied a breathtaking boldness of flavour. Intense but clean, the ingredients didn’t so much sing as wallop: the taco’s explosion was like being punched in the face by Queen Mab.

Cheese is very much part of the Soca diet, and it appeared again in a celeriac “pizza” and an oozing buckwheat beignet with fermented ricotta and porcini, dusted with more desiccated mushroom, a scalding ooze of autumn which contrasted perfectly with the languorous opening of the second service, cold almond soup with langoustine, fermented tomato and peach. Tiny raviolis of suckling pig with cherry and elderflower combined sweet, densely juicy meat with pasta as taut and ripe as the flesh of the fruit.

Unusually, Ros opted for another fish course after the meat, a trilogy derived from mountain trout amongst which a translucent cracker-boat of dried skin with trout liver bottarga was particularly vivid — creamy, delicate, with a ferrous shadow that perfectly anticipated the next course, a tartare of Dreznica lamb with wild mustard.

Ros is strict about the geographical range of her produce, eschewing any imported “luxury” ingredients, which not only feels particularly current but renders her imagination all the more impressive.

The confines of her larder might be physically relatively limited but Soca’s history is very much present; for the Romans the Julian Alps were the frontier between the eastern and western parts of the empire, and Ros referenced the presence of the legions in the dinner’s crescendo, a tiny fillet of rare roebuck in a beeswax and bee pollen garum.

Garum, not dissimilar to Asian fish sauce, was the staple umami base of the ancient Greeks, Romans and Byzantines, and its presence here was a brilliantly soulful reminder of the complexity of Europe’s food inheritance. This was one of the most sophisticated, elegant dishes I have ever tasted, the scent of wax against the blood of the meat creating a rich, honeyed, unique perfume, elevated even further by a Slovenian Pinot Noir, a Marjan Simcic 2015.

Ros’s husband, Valter, is the sommelier at Hisa Franko, and has been a champion of natural wine for 20 years. Amongst the 600 wines on the list, 90 per cent are organic and biodynamic, and Valter is passionate about introducing guests to their still unexpected flavours and rhythms. The selection of wines by the glass includes five “skin on” wines to encourage the cautious.

In its combination of rustic simplicity and world-class cooking, there’s something otherworldly about Hisa Franko. Maybe it’s the location, maybe the Puckish spirit of the chef herself, but the whole is so harmonious that it’s difficult to isolate a discrete element which explains exactly why it works so sublimely.

“Consult the genius of the place in all,” Pope advised, and though it might be difficult to locate Hisa Franko’s presiding deity, its taste will linger with you all the way down the mountain.

Hisa Franko, Staro selo 1, 5222 Kobarid, Slovenia. +386 5 389 41 20 www.hisafranko.com