Stachys affinis. Crosnes du Japon or Chinese artichokes are delicate nutty-flavoured tubers that appear quite often next to the Jerusalem artichokes (topinambours) in the larger French supermarkets and high-end grocers.
First cultivated in Europe in the town of Crosne (Essonne), they were quite popular until their proclivity for spreading like a weed made farmers think again.
Crosnes du Japon have a very short shelf life because of their thin skin; when the French use them (raw, pickled, dried or cooked), the dish is known as japonaise (crosne arrived in France via Japan, although it originated in northern China—hence the confusion).
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