Burl Smith wrote: "Although potentially fatal if eaten raw, Gyromitra esculenta is a popular delicacy in Scandinavia, Eastern Europe, and the upper Great Lakes region of North America. Although popular in some districts of the eastern Pyrenees, it is prohibited from sale to the public in Spain. It may be sold fresh in Finland, but it must be accompanied by warnings and instructions on correct preparation. "- Wiki Gyromitra Esculenta
Is it really Brain Mushroom? I looked it up before posting and some of the pics look quite different. Gyromitra esculenta seems to be darker with stalk, and much smaller. This is just a hemispherical blob the size and shape of a human brain.