Do you have a photograph of the fungus?

We do need a photo...

Whatever it is it will soon disappear on its own. The main part of the plant is underground and destroying the fungus would have no effect on it. If you don't like it just remove it manually but be prepared for it to reappear next year.

That only applies to toadstools/mushrooms, Steragram...

True - say fungus to me and I think toadstool, probably because I really like them...