The earliest recording can be traced back to 1959, from an album called The Sounds of Camp. This was added to the Smithsonian compilation A Fish That's a Song. No copyright or author credit is given on the Smithsonian release, and to this day, the song remains an anonymous piece. It does seem obvious that the work started as a kind of American folk song in summer camps, but this is speculation based on the information available. The disgusting tune was a hit anyway, and millions of kids began changing the lyrics to make it even more disgusting and entertaining.
The idea is simple enough: just combine body parts, dead animals, and other unsavory things and make it fit the beat. I first heard the song in a collection entitled Spooky Tunes! (which is the book I was trying to remember back in my very first post). Although the first line is always the same, each version adds different phrases to the chorus, and sometimes a different ending line as well. The version I'm familiar with is called "Spooky Stew" and features this first stanza:
Great green gobs of greasy grimy gopher guts
Scabs, scratches bumps and cuts
Yuck it sounds disgusting but
Just throw them in your musty rusty crusty pot and
BOO! It's spooky stew
You can view several variations on the song's Wikipedia page. Yes, Great Green Gobs has a Wikipedia page. Gotta love the internet. It's a gross song, sure, but man does it give me fond memories of my junior high years. Next time someone asks you what you'd like for dinner, start belting this little ditty and see how they react.