From the Super Mario Wiki
Chuckola Cola is a popular drink found in Chucklehuck Woods from Mario & Luigi: Superstar Saga. There is another rare variety called Chuckola Reserve, which is needed to cure Queen Bean. It later appeared in Paper Mario: The Thousand-Year Door as Admiral Bobbery's last request.
There are some appearance inconsistencies with Chuckola Cola between Mario and Luigi: Superstar Saga and Paper Mario: The Thousand-Year Door. Although actual bottles of Chuckola Cola were seen very rarely in Mario and Luigi: Superstar Saga, several were seen in the S.S. Chuckola, an ancient boat bound to ship Chuckola Cola across the world. Perhaps coincidentally, the Chuckola Cola was bottled similarly in both games, but it was colored differently: the Mario & Luigi variant was blue (but known to be red when seen en masse) and had a pink label while the Paper Mario: The Thousand-Year Door cola was purple with a yellow label. Since three different colors of Chuckola Fruit grow in Chucklehuck Woods, it is possible that the soda color depends on the type of fruit used to brew it.
In Paper Mario: The Thousand-Year Door, Admiral Bobbery wants a Chuckola Cola as his last request. When Mario asks Flavio about it, Flavio agrees to give it to Mario, but only if he could give him something in return. Mario gives Flavio a coconut, and they trade the items. Mario then gives it to Bobbery, and Bobbery joins Mario in his quest.
Brewing Chuckola Cola (Mario & Luigi: Superstar Saga)
The entrance of Chateau de Chucklehuck has four statues, each giving four different steps to brewing Chuckola Cola. These are the four different steps:
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