We have grown more varities of chard than I knew existed. In the kitchen garden you will see Rainbow\Bright Lights, Silverbeet, Spinach Beet. On the other side of the garden we have what the French refer to as Cardes. The wine bottle pictured is for perspective, not because of a wild party in the vegetable garden.
You'll see cardes in French markets with the leaves bundled on top of each other. The stalks have an excellent flavour and can be substituted in any recipe that calls for cardoons (for the first month, that's what I thought I was growing).
Most chard recipes will tell you to cut off the stalks leaving just the spinach-like leaves. The leaves can be treated like spinach, see Suggestion below. What the recipes neglect to mention is that when you discard with the stalks, you dispense with the essence of chard, because while the leaves are good, the stalks are wonderful. This recipe shows you one simple way to cook them.