A derogatory phrase used when a person does something idiotic, incompetent, unintelligent, foolish and or mindless. It implies that the person is mentally disabled or retarded and therefore this is the food they should eat.
Person 1: Bro why did Randall over there just stuff his head in that pile of feces?!
Person 2: I don't know bro but he needs some green jello.
“Green Gonzo” or “A green gonzo” is the act of using a snot rocket shot from your nose to your hands to be used as lubrication before sexual intercourse.
I was out of lube and had cotton mouth so bad I had to green gonzo Becky.