These are, by almost every barometer, happy animals, inhabiting a space almost unimaginable to most agricultural projects. All the dehesas which supply Cinco Jotas, Spain’s oldest jamon Iberico de bellota brand, demand a minimum of two hectares per animal. That’s 20,000 square metres of space to roam, happily snuffling and digging for their favourite food: acorns.

We detour off an ancient walkway called a camino into a fenced-off dehesa, through a rusty gate and past an ancient guard dog more interested in a siesta than security. The pigs immediately head towards us, seemingly most interested in sniffing our shoes, tiny piglets following their parents in a riot of squealing and excitement. These black-haired Iberico pigs normally live in groups of between 40 and 50 and Cinco Jotas works with hundreds of farmers who raise them across the region.

Most commercial pigs are killed at six months, but here the animals live much longer, between 18 and 24 months, until they weigh about 175kg. Government vets oversee every animal in the extensive curing and ageing that follows their slaughter.

Only after checking that they are 100 per cent Iberian acorn-fed and disease-free do they get the celebrated “pata negra” black label on their feet, the “norma de calidad” or quality standard.

The legs are taken to the salting room, where they spend one day in salt for every kilogram of weight, before being rinsed and put in drying rooms. They are finally left to hang from the ceiling in their thousands in the extraordinary, cavernous underground cellars, elegantly tiled in blue, white and terracotta.

The critical drying process takes a minimum of 36 months, but some clients wait up to six years before claiming the legs; there’s even a connoisseur’s market for vintage ham, with slower ageing making them rarer and pricier. The legs are exported around the world, either whole – the only way it can be imported into the US – or presliced by expert ham carvers known as cortadores who spend years learning how to cut the thinnest and most translucent slices.

More than 11,000km away in Hong Kong, Tsim Sha Tsui seems light years away from the dusty dehesas of Huelva, but here too there are serious connoisseurs – and plenty of fans. San Sebastián native and executive chef at The Bostonian in the Langham Hotel, Pedro Samper, explains the resonance of this very special ham.

“Jamon Iberico is the pride of Spain and has been appreciated in my culture for centuries. We’ve perfected the art of cured meat as a culinary tradition and its amazing flavour is a great snack at any time of the day – as well as a way for people to socialise and enjoy together.”

Indeed, jamon Iberico de bellota is served first at all important Spanish celebrations, including weddings, baptisms and at New Year.

Unlike most expensive and exclusive gourmet produce, there’s little in the way of etiquette or rules about eating it. In Jabugo, the town in Huelva that is the centre of Spain’s jamon Iberico de bellota industry, it is served simply sliced on a plate. When I ask the best way to try it, the answer couldn’t be clearer. “Take some with your fingers and put it straight in your mouth.”

The years of dedication, care, investment, fresh air – and acorns – pay dividends in an extraordinary mouthful. A gentle wave of umami, distinct notes of sweetness and nuttiness, a creamy finish without being oily.

Another chef who knows more than most about Spanish ham is the multi award-winning Jose Pizarro from Extremadura, the region which borders Huelva. His three London restaurants – as well as his previous work at Brindisa in London’s Borough Market – have won him legions of fans for simple, unpretentious renditions of Spanish classics.

“I just want to showcase the qualities of Spanish produce, keeping it simple with the best ingredients. If I was going to have jamon, it had to be the best in the world, and with jamon Iberico de bellota the character and flavour of the meat varies every year, depending on everything from the quality and number of acorns to climatic conditions.”

Taste and flavour are imparted by the environment where these humanely treated animals are raised.

Where to buy the ham in Hong Kong

Here are some hot spots for jamon Iberico de bellota:

Estudio

Estudio sells Cinco Jotas (5J) at its tapas bar and stall in Pacific Place.

Great Food Hall, Pacific Place, Admiralty. greatfoodhall.com

Reserva Ibérica HK

An extension of the original Barcelona shop, it offers a wide

range of jamon Iberico, carving workshop, wines and more.

15 Upper Station Street, Sheung Wan, tel: 2110 4868. reservaiberica.hk

Emtex

This online site sells Spanish wines and produce online including five-year-old jamon

Iberico de bellota from Don Ramón for HK$7,800

emtex.com.hk/collection/spanish-ham

Citysuper (15 branches in Hong Kong)

Stalls within its supermarkets carve jamon Iberico