Melt butter in the skillet, then add broccoli. Stir to coat and cook for about 4 minutes, until broccoli starts to soften but still has a crisp bite to it.
Sprinkle Ranch mix over broccoli. Add about 2-3 tablespoons of water and stir to coat broccoli completely. Cook for about a minute. If you prefer broccoli to be very soft, cook a couple of minutes longer.
Sprinkle Parmesan cheese over broccoli and serve hot.