Black grams come from South America. It is one of the ingredients of many Mexican and Brasilian recipes (such as in the Brasilian feijada). It is now widely spread. It is commonly used in Asia, in the making of the black sauce for instance. It can also be added to your curries and masale recipes.
About 100 g per person.
Soak the black grams for 12 to 16 hours and throw the soaking water.
Add 2 and a half volume of cold water without salt.