This Tumblr thread discusses the connection between Powerpuff Girls villain Mojo Jojo's note-writing speech patterns and the language of the Lex Luthor 40 cakes meme. The Super Dictionary itself was a 1978 comic book dictionary featuring DC comic book characters describing various words in context. The language itself, meant to be more demonstrative of the use of a particular word, rather than entertaining or succinct, feels stilted and weird. One excerpt of Lex Luthor stealing 40 cakes gained popularity as its own meme because of the inherent absurdity of the whole thing. How dare that bad, bad man take all those cakes. He couldn't possibly eat them all himself.
This thread posits that Mojo Jojo's letter-writing is directly influenced by this style of over-descriptive educational writing aimed at children. And with the two side-by-side, it's really easy to see the comparison. Leave it to Tumblr to look for such specific connections like this.