Homemade Plain Soy Yogurt

From "Artisan Vegan Cheese" by Miyoko Schinner

1 qt. plain soy milk
2/3 cup raw cashews, soaked 3 hours and drained
3 Tbsp plain non-dairy yogurt (preferably homemade, from your last batch)

Directions:
In a blender, whiz the cashews and 1 cup of the milk until smooth and creamy. Put mixture in a medium-sized heavy saucepan and whisk in the remaining milk. Cook over low heat until mixture is 110 degrees – no more!
Whisk in the yogurt, mixing completely. Pour into glass jar(s) – [1 qt. + 1 pt. canning jars work] and store in a dark warm place 4-8 hours, until set. (A gas oven with a pilot light is perfect.) Once set, refrigerate.