I read somewhere that swiss chard gets more bitter with time. You want to eat it fresh as in within 3 days of it being picked.
I also found this somewhere...
Quote:
Chard pairs well with eggs, in a frittata or tart or quiche. I like Deborah Madison's saffron chard tart recipe from the Greens cookbook. Not much cheese, so the vegetable really stands out.
If it's too acrid for your taste, consider giving the stems a fresh trim of at least an inch, then soaking the whole leaves in cold water for 20 minutes to perk and sweeten them up, as you would salad greens. Remove the stems for most uses. I also like the suggestions of adding raisins to the saute, a nice complement. The flavor is more mineral and a little more acrid than spinach, though they shouldn't be outright bitter unless the weather is hot and they're not being watered.
so maybe it's a matter of getting it some water to sweeten it up.
I've cooked it. It's not as tough as kale and I see that as a negative for my purposes which is to put it in a soup. I think chard is best steamed for a little while and then served with butter salt and pepper. I've tried it in soups and stews but it's a little too wilted for me.