So, how do you make natto? It's very easy. What you need is:
2 c organic dry soybeans
1-2 T natto starter [store bought natto should be ok to use]
1. Soak the beans over-night.
2. Cook about 45 min. in a pressure cooker or pot for much longer.
Don't over-cook. They shouldn't be mushy.
3. Add the natto. Stir well.
4. The mixture needs to be kept at 100-105 F for at least 24 hours.
5. A good way is to put the whole pot into the oven with a light bulb on. Or you can put a heating pad around the pot in a cooler.
6. After 24 hours it should be slimy like my picture shows. You can freeze in small bags. It should last at least 6 months.
Enjoy.