On the way to the toilets in the Real Food Cafe is a corridor where the walls are papered with appreciative notes from customers past.

Thrillingly, there’s a signed snap from Aneka, who had a number one hit in 1981 with Japanese Boy. Surely you remember her? In real life she was Mary Sandeman, a singer who’d had a healthy, heather-tramping career in the knobbly walking-stick world of Scottish folk but who then weirdly re-emerged on Top of the Pops as a singing geisha girl. She was the ultimate one-hit wonder, a musical footnote that Lieutenant Pigeon could only gaze upon with mute envy.

The thrust of Aneka’s song was simple. Despite the obvious gap in age, language and appreciation of the ancient Samurai ethics she was in love with a Japanese boy who had mysteriously vanished. Naturally this disappearance dismays and perplexes Aneka. There’s every possibility, of course, that the Japanese boy has stumbled across photographic evidence of his girlfriend consorting with The Corries and Jimmy Shand and has quite understandably entertained second thoughts about the whole thing. Either way, he has gone and Aneka is distraught: “A word of explanation, that’s all,” she warbled “It would stop me climbing the wall.”

The Real Food Cafe in Tyndrum is something of a culinary cult, the top of a hit parade of one. You wouldn’t come across it were you not driving out of Crianlarich, preparing yourself to traverse Rannoch Moor before passing through the lowering valleys of Glen Coe. Tyndrum styles itself the gateway to the Highlands. This means, in practice, that it’s fairly naff, an agglomeration of “fun” pubs, burger huts and tartan troll emporia, all designed to sate the average family until it reaches Fort William.

The Real Food Cafe doesn’t look particularly different. It was a derelict Little Chef when Sarah Heward and the late Steve Wolsey found it five years ago. Set by the side of the road it’s a prefab shack that seems to wince when the lorries thunder past.

There’s a slightly odd and fervid self-regard to the cafe, a sandal-wearing preciousness. The room is dominated by two massive central tables designed to encourage communal eating, which is a polite euphemism for watching total strangers pick crusts from their beards. Signs and boards seem ceaselessly to be affirming that we’re indulging in an experience that’s deeply benign and nurturing for everyone involved. Everything is sustainable, particularly the vexatious eco-chivvying. The proprietors talk on the website of their “gospel”, which essentially is all about how lucky we are to live in a world abundant with sausages and wholemeal oatcakes.

It is, to be fair though, God’s chip shop, the absolute acme of cared-for fast food, served by staff who have a stake in the enterprise, sourced from suppliers down the road, an establishment integrated holistically into the local community.

The large haddock supper (of course there’s a gluten-free version too) is text-book and dictionary-definition, a catcher’s-mitt sized sheet of meaty white fish in a batter that was dry and light.

There was a feisty scarlet Mediterranean fish soup made from the piscine kitchen scraps, a bit rough and rudimentary but terrific for £3.50, and salad based round a chunk of dark, oily Salar hot flaky smoked salmon from South Uist.

A steak and kidney pie was in a foil dish and deep-fried but well above high street standards. The rich, spicy haggis was made from cattle reared on Hindersay island in Shetland. There’s little skill or finesse in this species of Scottish street food, of course. But where there’s even the tiniest bit of scope for skill and finesse the Real Food Cafe capitalises with a passion and sincerity that’s truly impressive.

The Real Food Cafe, Main Street, Tyndrum, 01838 400 235, dinner for two with drinks £40

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