Can't find the right thread to put this in, but wolfy, I would DISPOSE OF those fiddlehead greens. Dump the things in the trash because they are not fit for human or animal food
Full of toxins most of them. Thiaminases are most common, along with hydrogen cyanide, an unknown toxin in some of them, and in certain ones a really nasty compound called ptilaquoside, an illudane glycoside thats both highly toxic and carcinogenic. Haemolytic, targets red blood cells, can cause blindness, and damages DNA.
You of all people should avoid eating these. I know some people do eat them but they really are not food. They are poisonous and only careful and thorough treatment enables them to be eaten with any degree of relative safety whatsoever. The thiaminases are enzymes, so should be denatured by prolonged boiling, throwing the water and boiling again.
Make me think of false morels they do, in that people's sensitivity varies hugely, but considering your health and the mode of action of some of the crap in fiddleheads, you really shouldn't be eating them. Ptilaquoside is so nast that even the water table is thought to become poisoned where rich stands of ptilaquoside containing ferns, bracken especially, male fern is also very poisonous, in bracken rich areas, the incidence of stomach, mouth and throat cancer skyrockets. Even amongst those who don't eat them.