Why cook chard stems in water with flour?
I cooked my chard stems in water in which I had whisked 2 tbsp of flour, as Deborah Madison recommended. So why the flour?
To the best of my knowledge, Deborah Madison's recipe for Swiss Chard creates a Gratin. She makes a basic bechamel, with flour of course, and combines the chard into that with other ingredients. I'm not acquainted with the recipe you refer to. Can you provide the details and the source of the data?
Its called a blanc, and its used mostly to preserve color in things that discolor easily. Its most commonly used on things like artichoke hearts, fennel bulbs etc.
EDIT Someone beat me to it!