Fermentation

No, I don't remove the skins from the chickpeas. I just cook them in water with half a lime or a tablespoon of vinegar, and then drain the water and wait for the chickpeas to cool. Then I add the spore/rice powder, mix, put them into perforated bags, and place in the home-made incubator.

Bonus tip: the liquid that is left behind when cooking the chickpeas is called aquafaba and it can be used as a vegan replacement of egg whites when making mayonnaise, meringues, and many other recipes. If you want to make the aquafaba without the acid, you can also add the acid to the chickpeas after collecting the liquid, or you can not add the acid at all.

I usually boil a 900 g bag of dried chickpeas for about 1 hour, with a tablespoon of vinegar added. Then I place the chickpeas into a large colander for them to cool and dry, and then I disperse a tablespoon or two of "starter" on them. I then put about 300 g - 400 g of inoculated chickpea into perforated ziploc bags, and hang these bags using clothpins in a 'chamber' that I made (it is a plastic tub with insulating foam, a hole through which a ceramic bulb heater goes in, and a cheap temperature controller that controls the chamber temperature to around 30 C).

This is a photo I have from a recent (FAILED!) experiment trying to 'scale up':

And this cover goes on top:

Imagine this, but with half the amount of tempeh. In this experiment I tried to make !3.55 kg of tempeh at once (8 tempeh), but they were touching each other, and the contact points of the tempeh turned wet and acidic - either it became too hot, or poor airflow allowed the bacteria and not the fungus to dominate those areas.