I am still not sure why El Bulli made me cry. Or at least how it magicked a hot tear to my eye. It wasn't the intensity of taste, with shifting textures and notes that lasted longer than Pavarotti's C. It wasn't that I felt I had to close my eyes in a crowded room to savour and surf every wave of flavour. It wasn't even that "peas 2011" tasted more like my first peas than in any dish I've eaten since I was seven. Nor was it, honestly, the toasty flow of Dom Pérignon 1973. It was simply, in the end, I think, the deliciousness that undid me.
Not all the dishes were sublime, of course – I am not sure chef Ferran Adrià is interested in that. He wants to make you think and to feel food, to orchestrate your mood, mess with your idea of what it could and should be. More flavour theatre than restaurant. We ate a Felliniesque, insane 50 dishes culled from Adrià's "greatest hits", the oldest from more than 20 years before, the newest only finalised that morning (the menu was revised six times). Plus endless choices from a giant chocolate box that looked like a flashing organ coming out of the floor. But if we pass over the Japanese-style tiramisu (a sleight of hand with miso that was plain unpleasant), the disappointing trademark carbonara tagliatelle, and the "challenging" frozen gorgonzola balloon, El Bulli's 50 cooks still sent out close to 50 plates of food for 50 people that no other restaurant may ever match. As Ferran Adrià's heir apparent and current number one cook in the world, René Redzepi of Copenhagen's Noma, tells me: "Ferran and his team are culinary freedom fighters. They helped free me."
Our superluxe Spanish food trip started, surreally, in Luton, in an anonymous single-storey airport building where celebrities and top business people avoid civilians and waiting for flights. We had just missed Ozzy Osbourne shuffling though the lounge, and then Simon le Bon suddenly couldn't come. But 30 minutes before takeoff on our private jet – like a top-end Lexus limo with wings – actress Rosamund Pike has heroically stepped in for the year's hot meal ticket: an El Bulli supper, pitch perfect for a selection of rare champagne, devised by Adrià with Richard Geoffroy, Dom Pérignon's effervescent chef de cave.
Later that day, over dinner in a private Catalan castle, I am sitting opposite Hollywood's Heather Graham and Jason Silva, her film-producer boyfriend, who have also flown in for the feast, watching as the star of Boogie Nights and The Hangover delicately transfers her food from her plate to her partner's. While the rest of us gorge on octopus, Iberico ham and vintage fizz, she is saved from starvation by a strawberry kebab.
But the star everyone is here to see is Ferran Adrià, the "best cook on the planet", according to Joël Robuchon, and he should know, with his world-record 26 Michelin stars.
"I never said I wouldn't feed people," Adrià smiles when I ask what he will miss when he closes his door at the end of this, his last season. "After July, El Bulli won't be a restaurant, not open every day. But I will still need feedback." Adrià's plan is for a nonprofit centre for "culinary creativity" opening in 2014, with a stream of new recipes posted on the internet. "We are excited," he says through an interpreter (Adrià doesn't trust his English to be precise enough for our purposes). "Bulli has always been about change. Why does Madonna with all her money need to earn more? She could share, not her money but her creativity. The young share, and we at the top should, too.
"When we started there were eight of us, all bachelors; now we have families, kids. I don't have children but I am very happily married, with a wonderful wife. With the foundation I can give something back – my talent, my luck. I have created 1,846 dishes – 80 per cent of new cookery techniques come from here – but no one can be number one for ever. Even those that love us get tired" – though this may be news to the two million people who desperately tried to book when the news of El Bulli's closure was announced.
"I will be 50 soon, with maybe 25-30 years left," he laughs. "I want to be happy like I have always been, and I can do this by taking away the things I don't like. Do what I want, when I want, for who I want."
I head into the El Bulli kitchen in time to catch the team troop in at 1pm, seven hours before service: heads bowed, hushed, intent. More like medieval novices come to mass than chefs about to prepare perhaps the greatest avant-garde meal ever seen.
Mateu Casañas, who has been with Adrià for 12 years, talks me through the preparation. Quietly, the chefs split into smaller teams. Ten start by teasing the germ from pine kernels, another six grade peas and skin them; 12 extract translucent filaments from sea cucumber to be intricately, delicately, lined into squares; four more sort papery yellow roses for perfect petals to be stuffed and steamed like dim sum. Seamlessly and almost silently, they shift between jobs, splitting young almonds to extract a jelly, making "parmesan frozen air".
I talk to Francesca, a Canadian of Asian heritage. On the day the call came from El Bulli she had been offered a staff position at Thomas Keller's three-star Per Se in New York. "So did I take a paid job in New York," she smiles, "or another 'stage' in Spain where I didn't speak the language?" And yet here she is in her second unpaid season, frothing and freezing buckets of cheese foam with a large grin on her face.
Jason Atherton alsoworked a stage at ElBulli, in 1998 when he was 27 – the year Adrià created his first foam. Before my trip to El Bulli we talk in the bar at Pollen Street Social, the British chef's celebrated new place in Mayfair. "I had worked with great chefs before," he says, "Marco Pierre White, Nico Ladenis, Pierre Koffmann, but it was from Ferran I learnt to question everything."
It took a full three years, says Atherton, before he realised how much his time at El Bulli had changed him: "There were 40 of us at the start of the season and at the end there were only 20 left. It takes a lot out of you, but the principles of how to run a great restaurant stay: the system, the time clock, the attention to detail. If I hadn't learn that, I wouldn't be here today.
"The sangria foam I serve at Pollen Street is the exact recipe I learnt, 12 years on. It is the lightest, airiest sangria you will ever taste. Why would I need to mess around with that? Chefs aren't geniuses, we are cooks," he says, "but Ferran deserves the mantle. A place like El Bulli will never happen again. It is impossible. One man's vision of what you could do with food."
Back in Spain, Adrià's relentless assault on my taste buds has driven me from the table overwhelmed, succumbed, surrendered, my hands and legs shaking, and we are "only" around 30 courses in. I have licked my plate of "gazpacho" and "ajo blanco", oblivious to my more reserved, more refined companions. I have tasted five of Geoffroy's dazzling Dom Pérignons, but I need respite before the two hare dishes, the "game meat cappuccino", the "blood", the "pond", the donuts, the other desserts and the "box".
I wander into the kitchen, where Observer photographer Howard Sooley is seven hours into his shoot – the first time Adrià has let anyone photograph behind the scenes during service.
Sooley used to work for US Vogue, and I watch as he slides between the chefs as they change direction like a shoal of silvery fish. And it strikes me: this is almost cooking as couture, backstage behind the catwalk as fantastical creations are pinned and primped into shape. I take in the dozens of tiny saucepans, the syringe-spiked dishes, a group of six young chefs intently plating up. All the cooks appear choreographed like a beautiful, complicated machine. Nothing is taken for granted, nothing is unconsidered.
There is true art in the artifice here, an underlying integrity to every technique. But somehow my celebrity-spiked supper has conjured up memories and emotions as much as the expected exquisite tastes. The plate-licked gazpacho is saturated with Spanish holidays. The peas take me back to podding on the porch with my mother in her yellow summer dress. The smell of the hare stock I will carry with me for ever.
At the perimeter of the kitchen, Ferran Adrià paces in silence, quietly observing. The general, seemingly unemotional, almost uninvolved. But watching. His eye seeing everything, like an eagle hanging high in the sky to catch the movement of every blade of grass.
He turns, sees me, too, standing there with lost eyes, and comes over. "Magic," he smiles softly, and he is right. As Jason Atherton says: "The guy is a legend, simple as that. We won't see his like again in our lifetime."
The 50 best: OFM's meal at El Bulli, course by course
beetroot and yoghurt meringue tomato cookie air baguette mojito - caipirinha sugar cane mojito and apple baguette gin fizz spherical olives mimetic peanuts pistachio ravioli parmesan cheese "porra" parmesan cheese "macaron" gorgonzola balloon olive oil chip flowers paper golden egg steamed shrimps with tea roses with ham wonton and melon water ham and ginger canape Japanese ravioli soy matches nori ravioli with lemon asparagus with miso tiramisu oysters and bone marrow tartar parmesan frozen air with muesli carbonara tagliatelle caviar cream with hazelnut caviar pine nuts shabu shabu "perrechico" cake polenta gnocchi with coffee, safran, skin milk and capers tender almonds perfumed with truffle barnacle with caviar two cooking prawns lulo "ceviche" and mollusk clam "ceviche" Oaxaca "taco" "gazpacho" and "ajo blanco" peas 2011 sea cucumber Shanghai lobster hare fritter game meat cappuccino blackberry risotto with game meat sauce hare ravioli with bolognese and blood pond yoghurt blini "coca de vidre" – crystal cake mini donuts apple rose box
Dom Pérignon Oenothèque 1973 Dom Pérignon Vintage 2002 Dom Pérignon Oenothèque 1996 Dom Pérignon Oenothèque 1969 Dom Pérignon Oenothèque 1976vDom Pérignon Oenothèque Rosé 1990
The timeline: 1961-2011
1961 El Bulli opens as mini-golf attraction in Roses, Catalonia, Spain. Owners Marketta and Dr Hans Schilling add a restaurant three years later.
1983 Ferran Adrià arrives for work experience at El Bulli, aged 22. Joins full-time the following year.
1987 Adrià becomes head chef; wins two Michelin stars within three years.
1990 The Schillings retire. Adrià and manager Juli Soler take over.
1994 Ferran forms development team devoted to innovation.
1996 "Chef of the century" Joël Robuchon, winner of 26 Michelin stars, declares Adrià to be his "heir".
1997 El Bulli wins third Michelin star. Adrià sets up a permanent development centre, El Taller - "the workshop" - in Barcelona.
2002 El Bulli voted best in the world by Restaurant magazine.
2004 Adrià named one of 100 most influential people in the world by Time magazine.
2008 Wins the Restaurant magazine best restaurant in the world award for the third year running, and for the fourth time in total.
2010 Ferran Adrià announces that he will close El Bulli in the summer of 2011 and set up an academy of culinary arts to open in 2014. More than two million people apply for a last chance to eat there.