All you really need to know about Heston Blumenthal is made abundantly clear in his toasted cheese sandwich. It's not the edible ingredients - bread, cheese, ham - that perplex, it's 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 was cooked longer than the filling to create a crisp, golden shell and perfectly melted - but not overmelted - 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 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, the other arm hanging like meat in a sling, courtesy of a shoulder operation that he's more or less just woken up from. Despite the painkillers and the fact that he winces as he draws his tea mug to his lips, Blumenthal is voluble and willing 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's bringing to Australia next month. His original restaurant, 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 which shatter glassily before collapsing into spudly fluff.