Jinnera

From Tardis Wiki, the free Doctor Who reference

Jinnera, or Jinnen Bean, was a common staple amongst the Tribe of the Three Valleys. It was typically made into a drink tasting of coffee and chocolate. Too much Jinnera would cause the muscles to relax, and an overdose would make one's heart simply stop beating. Two cups was the limit in an unspecified length of time. The leaves, pods, roots, and stems could all be used. The plants themselves were common throughout the forest. (PROSE: The Price of Paradise)