Nothing will prevent it from returning unless the plant is repotted with completely fresh potting mix, but even then, it's no guarantee. Fortunately, such fungi tend to only be a nuisance, and they eventually go away on their own; they don't infect the plant or cause root rot (the fungi that do that don't produce visible moldy or mushroom-y growth). One common fungus in indoor plant pots is the Flowerpot Parasol (Leucocoprinus), and it tends to flare up as the fungus decays organic matter in the potting mix, then subsides and disappears as it completes its life cycle. Removing only part of the potting mix won't work for long since the fungus inhabits most of (or the entire) the potting mix in the pot, so it will merely grow into the new mix you add. If the fungal growth makes the potting mix hard to water well (sometimes it can repel water), then you can try to repot by removing all old mix, rinsing off the roots, and repotting into fresh mix. (Be prompt once the roots are bare, as they are prone to drying out quickly.) Numerous fungal spores are always floating around the air (even indoors), and occur in potting mixes as well (none are sterile), so future flare-ups of this or similar fungi could occur again in the future. In our experience, though, it tends to come and go and not become a consistent problem.

Miri