Pork butt, I guess. No, really, just meat, human meat.
It wasn't the most inspired work I ever did, it was rather literal actually, but it had a surprising impact, in person, and among friends.
There seems to be a reticence to identify muscle as meat and these sorts of artworks, which are not uncommon, serve as triggers. At a base level, it forces an association between meat that is bought at the grocery store and the living tissue of the animal, through identification. That connection is disturbing for anyone not raised on a farm, apparently.
Just another emblem of the disconnectedness of modern life I suppose.