Jean-Loup. Not quite a usual name. Not quite a usual boy, either, with that dark, measuring look he shows to the world. His parents are divorced, I hear; he lives with his mother and sees his father three times a year. His favourite chocolate is bitter almond crisp – rather an adult taste, I thought; but then he is a curiously adult and self-possessed young man. His habit of watching everything through the viewfinder of his camera is slightly disconcerting; it’s as if he is trying to distance himself from the world outside, to find in the tiny digital screen a simpler, sweeter reality.

‘What’s that picture you’ve just taken?’

Obediently, he showed me. At first sight it looked like an abstract; a dazzle of colours and geometric shapes. Then I saw it: Zozie’s shoes, shot at eye level, deliberately out of focus among a kaleidoscope of foil-wrapped chocolates.

‘I like it,’ I said. ‘What’s that in the corner?’ It looked as if something outside the frame had cast a shadow into the picture.

He shrugged. ‘Maybe someone was standing too close.’ He levelled his camera at Zozie, standing behind the counter with a mass of coloured ribbons in her hands. ‘That’s nice,’ he said.

‘I’d rather not.’ She didn’t look up, but her voice was sharp.

Jean-Loup faltered. ‘I was just—’

‘I know.’ She smiled at him and he relaxed. ‘I just don’t like being photographed. I find I rarely look like myself.’

Now that, I thought, I could understand. But the sudden glimpse of insecurity – and in Zozie, of all people, whose cheery approach to everything makes any task look effortless – made me a little uneasy, and I began to wonder if I wasn’t relying too heavily on my friend, who must have her own problems and concerns, like everyone else.

Well, if she does, she is hiding them well; learning fast, and with an ease that has surprised us both. She comes in at eight every day, just as Anouk leaves for school, and spends the hour before opening-time watching as I demonstrate the various chocolate-making techniques.

She knows how to temper couverture; how to gauge the different blends; how to measure the temperatures and to keep them constant; how to achieve the best kind of gloss; how to pipe decorations on to a moulded figure or make chocolate curls with a potato peeler.

She has a knack, as my mother would have said. But her real skill is with our customers. I’d noticed it before, of course: her knack for dealing with different people; her memory for names; the infectious nature of her smile and the way she manages to make everyone feel special – however crowded the shop may be.