Soak the soybeans in clean water for 8 hours or more (overnight). I did mine after dinner and make the tempeh when I eat my breakfast. I find it better to do this in your pan to get less dishes to wash. Make sure that the water is at least 1.5 times your beans depth because the beans will soak the water in.

Throw the remaining water (use it to water your plants), replace with clean water, start boiling in medium heat for 30 minutes.

Add 1 tablespoon of vinegar to the water, keep boiling for another 10 minutes.

This will take some time, prepare your music or your tv/movie to watch. Dry the beans by putting them in between 2 clean kitchen towels. Press the towels to get the hulls off the beans. Take the hulls off, keep doing this until you think all hulls are off. Split beans are expected! You can mix the hulls in your stew or soup.

Ensure that the beans are both dry and cool enough, by leaving them between the cloth (if you can get different dry ones) for at least an hour. While doing this, you can prepare you resealable bag, puncture them using a fork, as many as you can in about 2cm radius for the entire bag.

Add half of the beans into one bag. Add half a teaspoon of vinegar and 1/4 a teaspoon of tempeh starter inside the bag. Mix well as if not, the spore won't be distributed properly, resulting in uneven sprouting.

If the weather is good and temperature is 25° or more, you can leave them inside a well ventilated box near your window (but not in direct sun) with a bowl of water. If it isn't, one suggestion is to put it inside an oven with the light turned on. Make sure that the room is not too cold at night. If you don't plan to use thermometer and oven/incubator, it's better to start your incubation in the morning for at least good temperature start.

In 48 hours, you will get your tempeh ready. It's ok to wait for another 24 hours, but if they are black sprouts (especially near your holes), it's OK to eat but it's a sign for you to put it inside the fridge and stop the incubation.

The tempeh is ready to be cooked! The easiest way is to dip it into salted, garlic water and fry. You can also dip it into a fry mix. They should last about a week in the fridge (better to cook it sooner though) and longer inside the freezer. You can reuse the resealable bags for your next batch.