Chocolate, of course, is not a new medium for artists. Think of Dieter Roth's chocolate sculptures, Anya Gallaccio's recent chocolate wall-coverings in a London gallery and Helen Chadwick's extraordinary Cacao, a huge, bubbling chocolate fountain, with defecatory references, which so enlivened the Serpentine in 1994.
What makes Antoni's chocolate different is that she has actually "eaten" it. Well, more precisely, she's bitten at it, chewed it, and spat quite a lot of it out. "I was interested in sculpting something with my mouth," she explains.
Antoni's aim was to make a work of art that focused upon bulimia - a chronic condition among American teenagers - and her chosen process was itself a commentary upon the illness: a re-creation of the bulimic's compulsive cycle of eating and vomiting.
She began by making a trip to the catering cash-and-carry and buying up a dozen 50lb bars of plain, unadulterated chocolate. She then tracked down the makers of the largest chocolate Santa Clauses in the world and persuaded them to cast her 12 bars into one perfect chocolate cube. This done, she had her raw material. Then came the fun bit.
For three days, non-stop, Antoni bit, nibbled, licked, pecked, munched, guzzled and snapped at her huge lump of confectionery. All that she didn't do was swallow. "I got blisters," she recalls. "My jaw was killing me." She barely made an in-road into the vast cube. Spitting out what she had bitten off, Antoni had enough chocolate left over to make a few smaller works of art as well. Her major creation, however, is Gnaw - the art you can enjoy between meals without spoiling your appetite.