ALL you really need to know about Heston Blumenthal is abundantly clear in his toasted cheese sandwich. It's not the edible ingredients - bread, cheese, ham - that perplex but the presence of ''new washing-up sponge (without scourer)'' on the list of necessaries. The questing Blumenthal mind decided the humble, well-loved toastie would be improved if the bread were cooked longer than the filling to create a crisp, golden shell and perfectly melted insides.
The solution? Squish a sponge between white-bread slices to create a cavity during an initial grilling. Then, remove the sponge and replace it with set fondue cheese and ham - and onion compote and truffle oil, if you like - for a second-stage melt. It's mad and it's wonderful and it's impossible to read the recipe, let alone make it, without giggling.
Blumenthal, 45, does plenty of laughing in an hour-long telephone chat. But he's serious about the pathway to fun, too, and he outlines a few of his many painstaking research projects in an obsessive's deadpan. He's at home in London with a headset microphone pressed to his cheek, a cup of tea in one hand and the other arm hanging like meat in a sling, courtesy of a shoulder operation from which he has more or less just woken. Despite the painkillers and the fact he winces as he brings the mug to his lips, Blumenthal is voluble and animated.
''I want food to be fun, exciting and delicious,'' he says. ''And I want to transfer any pleasure I get from cooking and eating to the diner.'' An extreme desire to relay pleasure underpins the British chef's four restaurants, seven books, six television series and the live show he will bring to Australia next month. His original baby, the Fat Duck, opened in Bray, Berkshire, in 1995. It gave the world snail porridge, bacon-and-egg ice-cream ''cooked'' with liquid nitrogen, an edible rose bush and much-copied triple-cooked chips that shatter glassily before collapsing into spudly fluff.
''The Duck'', as Blumenthal calls it with casual fondness, has held three Michelin stars since 2004 and is consistently named in the top-three restaurants in the world. Two pubs owned by Blumenthal, also in Bray, serve simpler British fare. Last year, he opened Dinner at the Mandarin Oriental, in London, where his interest in historical cuisine, also explored at the Duck, is allowed full flight. Blumenthal's initial impetus for the historical plundering came a dozen years ago when he stumbled on a description of a 14th-century dish in which a live yet plucked, basted and mysteriously slumbering chicken is presented on a platter with roasted birds, only to awake and escape, ''upsetting goblets and whatnots'' as it careens down the table.
Blumenthal does not hypnotise chickens but the absurd poultry performance is still his touchstone for dining-room theatre. The menu at Dinner includes cockscombs, cod cheek, cockles and a meaty morsel that looks like a mandarin but is chicken liver parfait in disguise. Like much of Blumenthal's food, it's a mix of trompe l'oeil and technology, sensory trickery and science, evocative fancies and intense industry.
Tickling many senses at once is the key: for the Fat Duck's ''Sound of the Sea'' dish, an iPod is served alongside a seafood medley. Diners eat to a soundtrack of crashing waves and squawking seabirds, causing many a nostalgic nibbler to subside into tears or gull-ish screeches of joy. It's food that explores how people remember, think and live, as much as it is a caressing of the tastebuds.
No one sounds more surprised than Blumenthal that Team Heston now numbers 330. ''This is beyond my wildest dreams,'' he says. ''My ambition was that maybe one day I would get a Michelin star.''
That was still an upstart ambition for a man who had never been employed in a professional kitchen. Famously self-taught, Blumenthal was impelled into restaurant life at 16 when he and his parents ate at the three-star L'Oustau de Baumaniere, in Provence. He has talked about that meal a lot. He has written about it many times. He could be forgiven for referring me to his website to crib the basics. Instead he launches into a misty reverie about ''the crunch of the gravel, the waiter with his handlebar moustache, the smell of the lavender'', reeling off the intoxicating details that coalesced in one driving thought: ''I will be part of that world.''
Blumenthal held on to that dream while he finished school, worked as a photocopier salesman, credit controller and repo man, all the while burying himself in food books and cooking like a maniac. He lapped up everything classical and French, then stumbled on food scientist Harold McGee's writings. McGee tore down a touchstone of traditional cooking by stating that searing meat does not seal in its juices. He might as well have denounced gravity. Blumenthal was rocked and energised in equal measure. Which other fundamental principles could be challenged by scientific investigation?
''I was like a kid questioning everything,'' he says, still gleeful. He unpicked ice-cream, he puzzled over chips. ''Every normal twentysomething wonders why chips go soggy, right?'' he asks. ''OK, I was a real trainspotter. Get a life, you sad person!''
The questions and investigations have continued apace and geeky sympathisers, including McGee, are now collaborators. With his squad, Blumenthal is putting the finishing touches to a domestic sous vide system he thinks has the potential to affect the home kitchen as dramatically as the advent of electricity.
Tickling many senses at once is the key.
Sous vide cooking requires a machine that vacuum-packs food in plastic and a water bath that cooks the bagged food at controlled temperatures. ''But there's something else this machine does, a really major uniqueness,'' he says enticingly. ''We're waiting for the patent to go through.''
He is as tantalisingly tight-lipped about the next TV series, to be filmed shortly. ''It's big, big over-the-top theatrical,'' he promises.
Blumenthal is less cagey about rumours that he may open a restaurant in Australia. ''I don't have any plans to but I would do it,'' he says. ''I like to open restaurants in places I love and I do love Australia.'' One thing he loves is our version of MasterChef, in which he has appeared, partly because he recognises himself in those amateur cooks who put it all on the line. ''I do have a fondness for them,'' he says. ''A lot of people are professionally cheffing because they fell into it. People who come through MasterChef are in it solely because they want to cook. And they give up nine months of their life for it. That's a whacking great commitment.''
So, would he have fronted up if this version of the show had been around pre-Duck? ''I don't know if I would have had the guts,'' he says. ''They're continually being dumped in these ridiculously pressurised situations. Cooking for myself at home didn't prepare me for the pressure I was letting myself in for when I opened the restaurant. If I did know, I think I would have bottled out.'' Instead he worked stupid hours, napping on piles of dirty laundry, seeing his three children and then-wife in harried snatches, pursuing hare-brained and brilliant notions, scrambling to make two implacable deadlines a day, lunch and dinner, questioning everything.
''Being self-taught gave me a child's naivete,'' he says. ''I thought I could have an upside-down mountain stuck on an aeroplane if I wanted it. I honestly thought everything was possible.''