Ferran Adria, of El Bulli fame, and Joel Robuchon, the most Michelin-starred chef in the world, have both declared this paella the best they have ever eaten.

Josefa Navarro was hunched over a large stove in the long, narrow kitchen of her restaurant, Paco Gandia, stirring a murky broth of rabbit and snails in a large paellera. The shallow pan was balanced on a small, blackened frame that overhung a bundle of fiercely burning kindling. It was hot, 80C, but Navarro wasn’t sweating. The fire spat and recoiled, but she was patient and serene against the wild gesticulations of the blaze. Experience has taught her to be this way.

Navarro has stood in this spot almost every day for 30 years. Each day she dresses in the same immaculate chef's whites that hang off her slender frame, and ties her auburn hair in the same tight ponytail. Each day smells like burnt wood and tastes like bitter saffron, and each day she makes the same paella from the same recipe for customers who have been visiting her for years. And it has to be this way; consistency makes her paella one of the best in Spain.

The hardest thing about cooking a paella is making sure it always tastes like the one before

"The hardest thing about cooking a paella is making sure it always tastes like the one before," Navarro said. "My customers come here because they want a paella that tastes like forever."

Her customers are some the best chefs in the world. Ferran Adria, of El Bulli fame, and Joel Robuchon, the most Michelin-starred chef in the world, have both declared Navarro's paella the best they have ever eaten. They appreciate its simplicity and marvel at its consistency. Indeed, in the age of frozen paellas in tourist-clogged cities, Paco Gandia has become a site of pilgrimage for serious gourmands searching for an authentic version of Spain's most symbolic dish.

It all began by accident in the village of Pinoso, where Navarro set up the small restaurant with her husband in 1985. She admitted that back then she had no desire to cook paella for a living, nor to be a chef of any kind. She knew how to cook because her mother had taught her, but it was not something of which she was excessively fond. Nevertheless, recently married and with lack of a better alternative in Alicante’s dusty interior, the pair decided to turn her skill into a business. It was, Navarro confessed, an uninspired decision that led to a life's work.

Before she opened her doors she decided she would not deviate from the techniques that her mother had taught her as a teenager – techniques that had been used by local families for decades. Like her mother, Navarro cooks the paella over a burning pyre of sticks cut from local grapevines called sarmiento; she uses only local products; and, most importantly, she employs few ingredients and extracts the maximum flavour from them.

Navarro has always been conscious of recreating the traditions and flavours of the region. She was never tempted to adopt the practices of Spain’s most famous rice culture in neighbouring Valencia, where rice was first introduced by the Moors in the 8th Century and paella invented in the mid-19th Century. Indeed, unlike the Valencians, who often pack their paellas full of myriad ingredients, from vegetables to seafood, Navarro’s recipes are more austere, reflective of the aridity of the region. It is little surprise then, that Paco Gandia offers only three paellas: one with vegetables, one with rabbit and one with both snails and rabbit.

"If you put too many things on your menu," Navarro said, "you end up spreading yourself too thin – being good at a lot, but not excellent at anything."

Unlike the techniques she uses, her cooking routine is very much her own. "In the kitchen, there is only me and my relationship with the paella," she said. Her day starts early, at 5:30 am. Firstly, she fries the rabbit, which she buys direct from a local slaughterhouse, and cleans the snails, which she picks from the rosemary bushes that populate the nearby hills. She then places the cut-up meat and the molluscs in large, brown ceramic pots. She adds water and begins to make a rich broth.

When the first orders come to the kitchen, around 2 pm, she lights the mini-pyre of dried grapevines and places the pan – the size of which depends on the number of the guests – on its stand. The sarmiento lights quickly, and when the flames are sufficiently fierce, she adds the broth of rabbit and snails to the paellera. After three minutes, when the liquid starts boiling, she pours in the rice. She uses senia or bahia rice, two Spanish grains that Navarro believes are the most difficult to cook.

"With this type of rice, there is a very short period in which it gives its best flavour and bite," she said. "It is very easy to ruin, unlike the more common bomba rice used in Valencian paellas, but it goes better with this paella."

Navarro then adds salt and three pinches of high-quality saffron, which turns the rice yellow and gives it its hay-like taste, and manipulates the stack of kindling underneath the paellera. She pulls it back and forth, adjusting the ferocity of the fire so that the flames spill over into the pan. "This way the rice picks up a hint of smokiness," she explained. Finally, she stirs the rice into the thickening stock; a technique frowned upon by most paella chefs, who leave the rice to rest.

After about 20 minutes, the liquid has reduced and the rice sticks flat to the pan. Navarro doesn't have to taste it to know it's done. She plucks the pan out of the fire and leaves it to rest.

She repeats this process between 10 and 15 times a day, so that by the end of the lunch service, at around 5 pm, she has been in the kitchen for 11.5 hours. "That's the reason that we are only open for lunch," she confessed. "I leave the kitchen exhausted."

Nevertheless, it is a period that usually flows without incident, without fuss and – except for the crackle of burning wood and scrapping of the iron pan – without noise. It is a routine in which she squeezes use out of every second, and with which she believes she has reached her maximum potential.

"I think that after all these years, I am making the best paella that I could make," she said. "My personal perfection has been reached."

Navarro, although grateful, tries not to get carried away with her mounting accolades. Her job has never been about glamour. She does not speak in the same romantic terms as the critics that praise her food, nor does she pretend to be one of the modern chefs that are elevating food to the realm of art. For her, making rice is just a job: sometimes she doesn't mind it, sometimes she hates it.

"I don't even eat paella anymore," she said sheepishly, "I've had too much of it in my life."

Navarro is a humble chef. She takes pride in satisfying her clients and is proud of her reputation. Beyond that, she is not sure what to say, except that when she returns to her stove tomorrow, she hopes the paella will taste the same as it did today.

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