“We sold one to someone in Hollywood,” says Gerhard, “but we had to declare it as an architectural model because you’re not allowed to sell food to the States.” Reaching up to a high shelf, he plucks down his latest prototype. It’s a box of Millennium Magic Cakes, tiny square sponges iced with, among others, images of a firework, a Champagne cork, a green alien. Such is its kitsch appeal, the Millennium Dome Cake has been a runaway success, even in America. It’s quite traditional, but the actual composition of the recipe is very “now” because it’s made without flour, and wheat allergies seem to be particularly fashionable at the moment.” The result, chewy cookies with a texture like macaroons, are bursting with almond and cinnamon flavours – the perfect accompaniment to mulled wine.The most forward-looking of his creations, is the much publicised Millennium Dome Cake – a crudely executed replica.

The pastry is always the same, but you give it a different look.”Under the watchful, mascara’d eye of Boy George, whose portrait, by the artist Stefan Biesenbach, hangs in the kitchen, Gerhard talks me through his recipes. “This one is a Cinnamon Star,” he says, “which you just wouldn’t bake at any other time of year. They give the cake a more contemporary look than, say, a robin.”Away from the bustling shop, in the tranquil white void of Gerhard’s architect-designed house nearby, he tells me about his true passion – Christmas cookies. “I’m not sure how far the tradition goes back in Germany,” he says, “but in Britain it was started by the Victorians. They became particularly popular after the war, because they could be made very cheaply. This year, we’ve discovered a supplier of a crystallised sugar that looks like sparkling granules, like glitter. Isn’t it lovely?”His other, highly-decorated cake was inspired by the jewellery designer Andrew Logan, a cakeaholic and regular visitor.

“I went to a sale of his,” says Gerhard, “and a couple of days later I saw a few fragments of gold- covered marzipan lying around in boxes which gave me the idea of making stars that looked like his jewellery. For most pre-Christmas depressives, however, cakes and cookies will have to do. At Konditor & Cook (konditor means pastry chef in German), there are some tempting remedies. “Our Christmas cakes are very English, very traditional,” says Gerhard, showing me a rich fruit cake topped with old-fashioned royal icing, “but we give them a modern twist.