This, then, on the subject of Icelandic cuisine -
"Another speciality was hakárl, the flesh of a huge Greenland shark hunted for the commercial value of its liver oil. The flesh which contains cyanic acid, a lethal poison, was rendered edible by leaving it buried in the ground for weeks until it rotted"
Now I will give it to you, some of my favourite foods and drinks are pre-rotted in various ways. I know how fish sauce is made and I still use it but how brave and how desperate would you have had to be to be the first person to try the rotten, poisonous shark?
I also wonder what it tastes like? Fishy cheese, perhaps? Please, no-one offer to send some, as I would feel obliged to try it.
*Kurlansky, Mark. Cod : A Biography of the Fish That Changed the World. Vintage, 1999.