Water chestnuts

The Chinese water chestnut (Eleocharis dulcis; synonyms E. equisetina, E. indica, E. plantaginea, E. plantaginoides, E. tuberosa, E. tumida), more often called simply the water chestnut, but not to be confused with the unrelated water caltrop which also goes by that name, is a grass-like sedge grown for its edible corms. It has tube-shaped, leafless green stems that grow to about 1.5 metres high.
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The canned variety are more widely available, but fresh water chestnuts are a treat that add incredible sweetness, juiciness and crunchy texture to a variety of Asian stir-fries, stews, stuffings and soups. Fresh water chestnuts have a dark brown-black skin that can be peeled away with a sharp knife. They should be firm with no soft spots.