Through the little country town of Machynlleth, just before the old Dyfi blast furnace and down the potholed lane through fields, woods and over the River Einion, you’ll find Wales’s best restaurant.

Though the setting is deeply rural — getting here by car takes three hours from Cardiff, more like six from London — those who have made the pilgrimage have long returned with rave reviews. And now it is official: in the latest Michelin Guide, Ynyshir (pronounced “unnis-heer”) has become the first restaurant in Wales ever to be awarded two stars.

Chef Gareth Ward grew up in rural County Durham (a picky eater as a child, apparently) and started working in a pub at 16. He moved up through various Michelin-starred establishments and came to Ynyshir with his partner (in business and life) Amelia Eiriksson back in 2013, when it was a more conventional country-house hotel. The owners overcame his initial reluctance by promising him free rein over the kitchen; he rewarded them with a first Michelin star in a year. Since then, the couple have taken a sizeable stake in the business, relaunched the hotel as a restaurant with 10 rooms, put up tepees and a tapas bar in the landscaped grounds and painted the house — which had always been white — a striking black, in keeping with the high drama of the cuisine.

Ward refines his food down and down, through boiling, ageing, pickling and even ultra-low freezing, until the flavours are amplified as far as they will go. Almost every dish involves an enormous amount of time and effort. Japanese Wagyu sirloin spends a month in Ward’s Himalayan salt chamber. The sourdough we eat for breakfast was proved for seven days.

In the hallway, soon after we arrive, a chef slides aside a hidden door in the front desk to reveal a sunken fridge and to introduce us to the ingredients. There’s a lobster and a crab, both landed a few miles away in Aberdovey, a slab of Wagyu so marbled it is almost white, a Japanese pear, an Irish duck the chef claims is the tastiest in the world, and an Italian white truffle the size of a toddler’s fist.

The meal begins in the bar at about 5pm, accompanied by an idiosyncratic mix of music — country, house and ’90s hip hop. The dishes begin to roll out. We savour thrilling mouthfuls of raw lobster tail in a hot Thai dressing and shrimps that have been tenderised by being frozen to -80C and then thawed.

A few plates in, black leather curtains are drawn back to reveal a little DJ booth where shelves are stacked floor-to-ceiling with vinyl and, beyond it, the dining room. Our cohort — there are 20 of us in all — sit at wooden tables in twos or fours, the places laid so that almost all guests face the kitchen, which is open and joined on to the far end of the room. The tableware is tactile: hand-carved wooden spoons and chopsticks, knives forged by a local blacksmith, lurid green moss in pots, and crockery by artist Sarah Jerath, who uses clay and stone that she digs up from the garden and ash she scavenges from the fire pit.

In the kitchen itself is a counter that seats four — it’s called Ffwrnais, meaning furnace in Welsh, a nod to the local blast furnace that smelted iron ore here in the late 1700s. It’s the best table in the house but tonight it’s empty: the guests who should have been here navigated instead to a village called Ynyshir in south Wales, two and a half hours of winding Welsh roads away. Heed this cautionary tale! It can take months to secure a table, and Eiriksson says that satnavs frequently misdirect guests.

There are no waiters: Ward and Eiriksson tore down the wall between the kitchen and the dining room so that chefs could flow seamlessly from worktop to diners’ table, introducing each plate themselves. “Did you say scallops poached in duck liver?” I stammer at one point. “Yes,” the young chef says with a smile, before describing the painstaking process.

After a dish of rich chilli crab served with a deep-fried steam bun and matured kaluga caviar, the kitchen barbecue flares, the DJ ups the tempo and steel flashes as the chefs sharpen their knives to mark the transition from marine life to meat. At this point, Ward’s two-year-old son totters into the kitchen to say goodnight to his dad. Ward scoops him up and continues cooking with the small boy in his arms.

Later, the lights dip, a chef walks past trailing wood smoke from burning birch embers, and a disco ball casts myriad dots around the room. Out comes a dish made from birch sap, tapped from trees in the garden and reduced by 98 per cent.

After eight tiny desserts, we savour our digestif in bewildered delight. In the hallway hangs a row of floor-length fur coats for guests to don as they drift out into the cool night. Ward is having a drink by the fire pit so we sit beside him and stare into the flames. “Is it always like that?” I ask, wondering if we’ve witnessed an exceptional tour de force. “Always,” he says, nodding solemnly. “It’s the only way.”

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