I started by working my way around Fortnum & Mason, Harrods and Harvey Nichols, arriving home with a collection of boxes tied with ribbon. Harrods' most exclusive chocolates are called Tschirren, which I found on the sweet side, with centres a touch too dry and crumbly for my liking. Fortnum & Mason sells a range by a Belgian chocolatier, Pierre Marcolini, who, as far as I can see from his photograph, is Belgium's answer to Jean-Christophe Novelli, complete with cod philosophy. His chocolates, though, are superb - built around daringly intense flavours such as jasmine, violet, lemon tea, cardamom and star anise. Curiously, for Belgian chocolates, they were the least sweet of all I tasted.
Traditionally, Belgian and Swiss chocolates are more sugary than the French, although they excel with their cream fillings. The supplier of the Ritz, a tiny company called Casemir which hand-produces chocolates to order, has fillings as light and flimsy as a mousse. These chocolates are absurdly indulgent - so huge you could almost eat them with a spoon.
A Belgian or Swiss artisan will argue that French couvertures are too fruity and overpower the filling. I disagree. In the right hands, and if the filling is assertive enough - a tangy lemon, deep raspberry or a healthy shot of liqueur, for instance - they can be stunning. Cracking through a crisp shell into a buttery ganache the consistency of soft fudge is, to my mind, how it should be.
The French chocolatier, Valhrona - which also produces a range of bonbons - seems to increase its British foothold by the week. Harvey Nichols' Fifth Floor has just renounced all other chocolates to sell only them. The presentation alone is light years ahead of any other chocolate - the Christmas selection is gilded with specks of silver and gold and fine writing. But if I have to state a favourite, then it is the memory of Pierre Marcolini's chocolates that lingers.
This weekend, you, too, have the opportunity to go mad at the International Festival of Chocolate, at London's Royal Horticultural Halls. Exhibitors range from Cadbury's to Melchior, a Swiss-born maker of delectable truffles. The consistency of his centres is pretty much perfect - you can pull it like molten glass. The Danish chocolatier Bojesen will also be there. "In Denmark, we have a tradition of nougat with marzipan, and marzipan with nougat," says Rasmus Bojensen, who is also a restaurateur at Tivoli in Copenhagen. Bojensen has created a range of spice ganaches - everything from curry powder and chilli to saffron and nutmeg. But, ironically, what he does best is a boxwood set of five pencils of marzipan covered in the thinnest dark chocolate. The consistency is more like a loose toffee than the dry grain, reeking of fake almond essence, that is the norm. One marzipan, combined with a pulp of dried figs and Cognac, is extraordinary. Others come flavoured with orange and cardamom, raisins and rum, sambuca and coffee.
I was disappointed, though, not to encounter at least one range of chocolates selling for an astronomical amount of money. So exotic and rarefied, they would have the gourmets of the world clamouring, knowing that to be given a box would represent an ultimate declaration of love. As it is, pounds 24 for the most expensive works out at roughly 80p a bonbon, which is less than the cost of a single nori roll in Tesco. Then again, I hadn't yet checked out Bluebird in the King's Road. Sure enough, Sir Terence came up trumps. He has an Irish chocolate truffle made by Skelligs Chocolate Company that works out at pounds 44 for half a kilo, although most of this accounts for the beautiful hand-painted box. So there would still seem to be a gap in the market
The International Festival of Chocolate is at the Royal Horticultural Halls, Vincent Square, London SW1. Today, 10am to 6pm; tomorrow, 10am to 5.30pm, entrance pounds 7.50.
Anthony Rose matches wine with chocolate on page 78