I've been eating a lot of greens lately, thanks to you and your chard suggestion.
I usually fry up some garlic (pre chopped, bought a bottle) in olive oil. Add a bit of salt and pepper. Stir in a slice of chopped onion and sometime a bunch of chopped (thickly) mushrooms.
Let that sizzle under medium low for a bit, while I work on the chard.
Slice up the chard, separating the stalk from the leaves. Slice the stalks in 3 inch slivers. Toss the stalk in the pan.
Cover. Wait about 5 minutes. Stir. Wait a few more minutes until the various pieces are almost not stiff / crisp.
The "almost" is because now it is time for the leaves to go in.
Put the leaves in, cover, wait 3 minutes.
Stir.
Enjoy.
I do the same recipe for broccoli rabb instead of the chard.
I'll have this type of recipe for a full meal 3 or 4 times a week.