Herring soup
From the 1881 Household Cyclopedia
Take 8 gallons of water, and mix it with 5 pounds of barley-meal. Boil it to the consistence of a thick jelly. Season it with salt, pepper, vinegar, sweet herbs, and, to give it a gratifying flavor, add the meat of 4 red herrings pounded.
It is a common practise in southwestern Sweden to spit three times at the "ring" of the pot, throwing the soup away if you miss. This comes from an old Swedish story and is said to stop the herrings coming alive in your stomach. Later studies show that this is just superstition and probably first started out when someone who ate herring soup got a stomach ache.