Koopa-Kola
Koopa-Kola (or Koopa Kola) is 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."
Koopa-Kola is first shown in The Super Mario Bros. Super Show! episode "Karate Koopa," where it is drunk by Karate Koopa and his minions at a short celebration party. However, it receives little more than a brief mention and is only seen very briefly.
Additionally Koopa-Kola is mentioned a few times in Nintendo Adventure Books. It is featured prominently in Unjust Desserts where a shrunken Mario finds a particularly large amount of the substance inside Yoshi's stomach. If he tries to swim across, the Koopa-Kola congeals into sticky crystals all over him.