Mississippi mud is a pie I think
You haven’t had any either??? LOL
I have an old Bell’s Best cookbook from the mid 80s. It is falling apart. It has recipes of pound cakes and all kinds of things that my mother and all the church ladies and neighbors made all my growing up years. There are three Mississippi Mud cake recipes in it. No pies. No brownies. I have never made any of them nor did my mother. I was always a fan of Coca Cola cake though. Whew. That stuff will kill ya. :-)