A leek is basically a gourmet onion plant, half of which is thrown away in cleaning.
Leeks originate from the Mediterranean basin where dried specimens and drawings found in Egyptian archaeological sites suggest they were part of the region’s diet since 2 BC. According to one chronicler, the Emperor Nero ate so many to improve his singing voice that he was nicknamed Porophagus, or Leek Eater.
By 640 AD leeks had migrated from the Mediterranean and were growing in Britain. Welsh warriors under the command of King Cadwallader placed leeks in their hats to distinguish themselves from the Saxons in battle. In the Middle Ages leeks stewed with honey were a remedy for those suffering from nasal congestion.