I got it with the granary. I wasted a good many attempts missing one obvious little thing on the first turn. Once i noticed what i was missing i got it on the next try. Spoiler : I forgot to screen cap the granary, but it's definitely there. The obvious little detail that i was missing was putting 1T into farming the bananas before moving into the forest. That's such an obvious thing too, but since i was completing ignoring the bananas in the original, non-granary method, i had kind of gotten set into the habit of not doing it.