In the comments section of the Vegetarian Potato Stew, commenter Mrs Belogski asks: “Aren’t you supposed to boil kidney beans rapidly for a few minutes to destroy a particular toxin which they contain?”
Mrs Belogski then found this explanation of toxins in kidney beans:
From http://www.vegsoc.org/info/pulses.html
Red kidney beans: Incidents of food poisoning have been reported associated with the consumption of raw or undercooked red kidney beans