How do I get my object to change colors randomly?

Hi guys.

This may seem like a basic question but I would like to see if I can get an answer. I have been looking online and don't seem to be having any luck.

So, a lot of my game consists around honeycombs that I created in Blender. I want these honeycombs to start out their original golden color but then I want to have it randomly change their color to black and then stay that way until clicked again when it reverts back to the original construct.

I hope that this is possible with Unity. Please help, and thank you in advance if you can.