Tempeh

Cover soybeans with water, and soak overnight or at least 12 hours.

Remove the hulls (i.e. skins) from the beans by rubbing between both hands (see notes).

Skim off most of the hulls either by washing them away or by using a skimmer or strainer. Some hulls may be left behind without affecting tempeh quality.

Cook beans until just tender, not mushy; undercooked is best for tempeh (see notes).

Drain beans, and spread to dry somewhere with airflow (see notes).

Collect beans into a bowl, and mix in the cider vinegar. This acidifies the beans slightly, inhibiting unwanted spoilage organisms during fermentation.

Sprinkle the tempeh starter over the beans and mix in well (see notes).

Pack the beans loosely into banana leaves, zip-lock bags, or shallow dishes for incubating. Zip-lock bags must be punctured at roughly 1cm / ½ inch intervals to keep oxygen up to the fermenting beans.