Melted maybe 1/8th stick butter on low in a big pan & mix in a good-sized lump of mustard.
Cut 1 bunch Swiss chard into stemmy part and leaffy part. Set the stemmy part aside (and boiled it in some white wine that would otherwise have gone to waste, just to see what happened) (answer: not much of interest).
Cut the leaffy part into about finger-long, finger-wide units. Stuck them in the pan and got the sauce on them. Cooked on medium until just short of tender enough to eat. Added salt until tasty and then some pepper. Added 1 cup leftover rice from fridge.
Turned heat up to max and stirred together until I got the impression the rice was warm.
Serves two, or me.