Because of the oxalic acid Swiss Chard should be cooked in boiling water or steamed before eating. To prepare Swiss Chard fold leaves in half and cut off stem. Chop and rinse chard. To boil, bring lightly salted water to a boil. When water is at a high boil add chard. Bring back to a boil and cook for about 3-4 minutes. Drain in colander. It is now ready to be eaten.