Soy milk is by far the most widely used alternative but not necessarily the best.
- 140 gm soybeans (ideally split soybeans)
To make 1 liter of soy milk put the soybeans in a pan and pour 3 liters boiling water over them. Let it cool and wait 6 to 12 hours. Drain the beans, add 1 liter cold water and mix it in a blender for 3 minutes. Remove the soymilk from the solids by squeezing the mixture through a cheesecloth. Bring the soymilk to boiling point and continue to boil for 10 minutes.
If you are making milks regularly, milk making machines are available in the US that are not very expensive and which are very efficient.