He had an advertisement for a new cereal, “Puffed Grass.”
“You may have wondered how we developed Puffed Grass cereal. One day our near-sighted gardener dumped the lawn cuttings into one of our puffed oat guns. The result... Puffed Grass. Yes, science is always working for you here at... “ (Don’t remember the name of the company he used.)
Then there’s a little jingle, followed by a guy who says, “You can always tell a Puffed Grass eater. He’s got a green mouth.” And then the sound of a cannon (Puffed Grass gun).
I remember that one!
Have you looked up his bio? I’d forgotten how many voice characters he’d also played (that did not have his recognizable voice).