I like them lightly sautéed in butter with a pinch of salt. They’re very delicate and don’t take much time in the pan at all.

But always make sure they’re fully cooked, never consume wild mushrooms raw (with very few exceptions).

There is also concern about consuming certain types of Coprinus with alcohol, but to my knowledge shaggy inkcaps are safe in that regard.

I’ll confirm and add that they should ideally be picked before the gills start changing colors at all, just white. And make sure you learn to recognize them so you don’t accidentally pick another type along with them.