Koopa-Kola
Koopa-Kola was a recurring product in the Nintendo Comics System Mario comics. According to a quote by Bowser, it comes in both plain and crunchy variety, and is "made from REAL coal."
Additionally, Koopa-Kola was shown in The Super Mario Bros. Super Show! episode "Karate Koopa", where it was being drunk by Karate Koopa and his minions at a short celebration party. However, it received little more than a brief mention, and was only seen very briefly.
Koopa-Kola is mentioned a few times in Nintendo Adventure Books. It is featured prominently in Unjust Desserts where a shrunken Mario finds a virtual lake of the stuff inside Yoshi's stomach. If he tries to swim across the Koopa-Kola congeals into sticky crystals all over him.
Trivia
Koopa-Kola is seemingly based upon Coca-Cola.
