Remove all such magic, though, and it's a sorrier tale. Come on, be honest, just how long has that tin been sitting in the cupboard, and when did you last look at it with anything resembling desire? I keep several cans in the cupboard in the pretence that next time I am in need of a snack, I shall turn to them - but I never do. Now and again, when we move house, I chuck them out and, having settled elsewhere, buy a couple more tins that sit around for another five years. So the quest this week to discover whether or not the tins of sardines sold in uppercrust haunts such as Fortnum & Mason and Fifth Floor Harvey Nichols at vast cost really justify their apparently inflated price, struck me as being something of a poisoned chalice.
In fact, I am more likely to buy tinned fish for the tin than for what's in it. Any jackdaw guilty of keeping cotton reels in empty Bendicks Bittermints boxes, or of saving the tin of Chocolate Olivers long after the last biscuit has been consumed, cannot fail to succumb to a tin of Connetable's sardines, which resembles a classy old tobacco tin. These sardines "preparees a l'ancienne a Douarnenez", have on the lid a black-and-white portrait of some aficionado declaring "Les Sardines Connetable!
Once you have peeled back back the lid (taking care that the ring-pull doesn't snap off, for what could be more annoying than hacking your way with an opener into a tin that wasn't designed for it?), you find inside the silver-skinned sardines shimmering beneath a slick of dark yellow oil. I can understand why the manufacturers of novelty confectionery should choose to make boxes of chocolate ones.
Of course, there was no point in tasting these superior fish without first tasting their cheaper cousins, the likes of John West and Princes. One reason I don't have a cat is that I cannot stand the thought of having to open tins of Whiskas to keep it happy, and I feel rather the same way about these sardines as I do about pet food. They have a tough, dry texture, which is why they're at their best mashed up with lots of butter - without it, they fail miserably to fulfil their ideal role as an impromptu appetiser to be eaten along with some quail eggs, radishes and gerkins, which can also be magicked to the table at the click of your fingers.
Diving into the tin of Connetables with my fork, I soon realised that here were sardines of an altogether higher order. The flesh is succulent and tastes of the sea, with a more pronounced flavour than the fresh ones, much as a dried porcini mushroom tastes more intense than a fresh one. If Uncle had had some of these to make his pate, it really would have been a star turn.
Connetable's sardines have an interesting history: "depuis 1853" this has been a family firm. It was founded by Wenceslas Chancerelle, and today its sardine cannery is the sole survivor in a part of Brittany that once boasted more than 30. Something rather strange happened here in the Sixties: the fish mutated, becoming too large to go into tins, so now they all come from the Atlantic and Mediterranean.
What sets Connetable's sardines apart, however, is the process - they are gutted by hand rather than by machine, and when the head is pulled off, the innards come out too.This fails to happen if a machine is doing the job, which is why you end up with sardines, guts and all. This is not a desirable state of affairs, as the guts rot and eventually taint and soften the flesh.
Moving on, the gutless Connetable's fish are then fried either in olive oil or in peanut oil, again setting them apart from the more commonplace steamed varieties.
And now, enter the connoisseur. If you doubt that there is any such thing, you cannot have encountered the Academie de la Sardine de la Saussaye in France, where tastings are conducted with an appreciation of vintage.
Raymond Mathias, director of Bespoke Foods, which imports Connetable's sardines, remembers how his mother would turn tins of sardines every six months. I don't know what sort of upbringing you had, but I certainly don't recall my mum doing this. The idea is that, over time, the oil penetrates the flesh and it matures; the backbone, meanwhile, is softened.
Connetable also sell "vintage" cans stamped with the date. At the moment, it seems you should be buying the 1997 vintage to lay down next to the claret for a few years. And to think I used to chuck out my old, unopened tins
Available from good food shops and by mail order from Morel Bros,Cobbett and Son (0171-346 0046; fax 0171- 346 0033). Sardines come in 115g cans: in extra virgin olive oil, pounds 1.85, boneless pounds 2.50, lemon pounds 1.85, vintage pounds 3.25, smoked pounds 1.35 (100g).