I need to make a chocholate mousse cake for a wedding. They want it covered with fondant. Can i do this and how do i do this.

Any advice is more than welcome
Thank you

They want chocolate mousse as a filling? If so, I'm assuming it would have to be refrigerated, and fondant does not get along with the refrigerator- It causes the fondant to 'sweat' and become sticky and gooey. However, Im still newer to decorating too, so there may be more experienced decorators with a better answer.