Away from its famed cerulean seas, Sardinia’s craggy interior is a twisting maze of deep chasms and impenetrable massifs that shelter some of Europe’s most ancient traditions.

Residents here still speak Sardo, the closest living form of Latin. Grandmothers gaze warily at outsiders from under embroidered veils. And, in a modest apartment in the town of Nuoro, a slight 62-year-old named Paola Abraini wakes up every day at 7 am to begin making su filindeu – the rarest pasta in the world.

In fact, there are only two other women on the planet who still know how to make it: Abraini’s niece and her sister-in-law, both of whom live in this far-flung town clinging to the slopes of Monte Ortobene.

No one can remember how or why the women in Nuoro started preparing su filindeu (whose name means “the threads of God”), but for more than 300 years, the recipe and technique have only been passed down through the women in Abraini’s family – each of whom have guarded it tightly before teaching it to their daughters.

But after an unexpected invitation to Abraini’s home, I found myself in her kitchen, watching her work.

I wasn’t her first guest, though. Last year, a team of engineers from Barilla pasta came to see if they could reproduce her technique with a machine. They couldn’t. After hearing rumours about a secret Sardinian pasta, Carlo Petrini, the president of Slow Food International, visited this spring. And this summer, British celebrity chef Jamie Oliver stopped by to ask Abraini if she could teach him how to make the dish. After failing for two hours, he threw his hands up and said, “I’ve been making pasta for 20 years and I’ve never seen anything like this.”

“Many people say that I have a secret I don’t want to reveal,” Abraini told me, smiling. “But the secret is right in front of you. It’s in my hands.”

Su filindeu is made by pulling and folding semolina dough into 256 perfectly even strands with the tips of your fingers, and then stretching the needle-thin wires diagonally across a circular frame in an intricate three-layer pattern. It’s so difficult and time-consuming to prepare that for the past 200 years, the sacred dish has only been served to the faithful who complete a 33km pilgrimage on foot or horseback from Nuoro to the village of Lula for the biannual Feast of San Francesco.

When I arrived, the October feast was three days away and Abraini had just finished making enough su filindeu to feed the 1,500 pilgrims expected to descend on Lula from throughout Sardinia. She worked five hours every day for a month to make 50kg of the pasta, and for the larger nine-day feast in May, she’ll prepare four times as much.

“There are only three ingredients: semolina wheat, water and salt,” Abraini said, vigorously kneading the dough back and forth. “But since everything is done by hand, the most important ingredient is elbow grease.”

Abraini patiently explained how you work the pasta thoroughly until it reaches a consistency reminiscent of modelling clay, then divide the dough into smaller sections and continue working it into a rolled-cylindrical shape.

Then comes the hardest part, a process she calls, “understanding the dough with your hands.” When she feels that it needs to be more elastic, she dips her fingers into a bowl of salt water. When it needs more moisture, she dips them into a separate bowl of regular water. “It can take years to understand,” she beamed. “It’s like a game with your hands. But once you achieve it, then the magic happens.”

When the semolina reached just the right consistency, Abraini picked up the cylindrical strand to stretch and fold the dough, doubling it as she pressed the heads of the su filindeu into her palms. She repeated this sequence in a fluid motion eight times. With each sweeping pull, the dough became thinner and thinner. After eight sequences, she was left with 256 even strands about half as wide as angel-hair pasta. She then carefully laid the strands on a circular base, one on top of another, to form a cross, trimming any excess from the ends with her fingers before repeating the process over and over.

When she’d formed three layers, she took the base outside to dry in the Sardinian sun. After several hours, the layers hardened into delicate sheets of white razor-thin threads resembling stitched lace. Abraini then broke the circular sheets into crude strips and packed them into boxes, ready for the San Francesco feast’s prior to place them in boiling sheep’s broth with grated pecorino and offer it as a thick soup to the pilgrims.

“No one’s really sure how this ancient tradition started, but it’s at the heart of the festival,” Stefano Flamini, this year’s prior, told me. “If there’s no su filindeu, there’s no Feast of San Francesco.”

But after more than 300 years in the same matrilineal family tree, these threads of God may need a miracle to survive for future generations. Only one of Abraini’s two daughters knows the basic technique, and lacks the passion and patience of her mother. Neither of Abraini’s daughters have daughters of their own. The two other women in Abraini’s family who still carry on the tradition are now both in their 50s and have yet to find willing successors among their own children.

“This is one of the most at-risk foods of becoming extinct, in large part because it’s one of the most difficult pastas to make that exists,” said Raffaella Ponzio, head coordinator of Slow Food International’s Ark of Taste, an initiative that aims to classify and preserve the world’s most endangered culinary traditions. Of the project’s 3,844 listed items, no other pasta is made by as few producers as su filindeu – making it both the world’s rarest and most endangered pasta.

“Conserving su filindeu isn’t just a question of a culinary art form, but also a piece of cultural identity,” Ponzio added.

Recognizing this, Abraini has done something previously unheard of with her family’s tightly guarded dish: she attempted to teach girls in Nuoro from other families how to make it.

“It didn’t go well,” Abraini admitted. First, she approached the local government to see if she could open up a small school, but they told her there was no money. Then, she agreed to invite students into her home.

“The problem was that once they saw how I actually do it, they’d say, ‘It’s just too much work’, and wouldn’t come back,” she said.

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Yet, Abraini refuses to let the tradition fade away, making it her mission to share su filindeu with the world. In the last few years, Italy’s premier food and wine magazine, Gambero Rosso, has invited her to Rome twice so they can film her preparing the dish. Recently, she’s begun making su filindeu for three restaurants in the area – and in the process, offering non-pilgrims a chance to taste it for the first time.

At one of those restaurants, Al Ciusa, her black squid-ink dyed su filindeu nero won Sardinia’s Porcino d’Oro prize for best dish in 2010.

At another, Il Refugio, it’s the most popular item on the menu.

“We have people coming from all over Europe just to taste it,” owner Silverio Nanu told me as I sampled the dish.

When I shared that news with Abraini, her eyes danced with delight.

Where to Try Su Filindeu If you’re in Sardinia between 1-9 May or 1-4 October, follow the long line of pilgrims to the San Francesco church outside Lula. Otherwise, try it at these three restaurants: If you can’t stay the night at Sebastiano Secchi’s Agriturismo Testone, at least pop in for dinner and taste the island’s best rendition of Abraini’s su filindeu pasta, served in mutton broth.

At the expertly run Il Rifugio in downtown Nuoro, owner Silverio plays host out front while his son Francesco whips up su filindeu in the kitchen.

Upscale Al Ciusa serves Nuoro’s only version of su filindeu nero, which Abraini invented by combining the pasta with squid ink.

“You know, for me it’s a blessing just to be able to make su filindeu. I’ve been in love with it since the first time I ever saw it, and I love it more each day,” she said. “I hope to continue to make if for many years ahead – but if one day I have to stop, at least I’ll have a video.”

Custom Made is a BBC Travel series that introduces you to custodians of cultural traditions all around the world.

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