What is a food that makes you think “How did humans discover this was edible”?

@dancingtongue Acorns too. They are extremely bitter until they have the tannins leached out with salt by boiling them in several changes of water. When I was 9 years old and home alone I collected a bowl of acorns and shelled them and boiled them in salt water. The water turned black. I did it a couple more times and the water was clear. Then I baked them on a cookie sheet like roasted peanuts and ate them. I had no one to tell me how to do it, it was an experiment. I think the genetic memory from my Cherokee ancestry came into play on this one.