I am doing a stacked chocolate cake this weekend. I will use American chocolate buttercream and they want the entire cake covered in ganache - I will pour it on. I have done this before but only with it drizzled down the sides. This time, they want the entire thing covered. I know how to do it, no problem, but I don't know if I need to refrigerate after I do it? Could it sit out overnight? I will, of course, cover it with an airtight container. I just didn't know if it will go bad since it has heavy cream in it.

Thank you in advance for any help. Just want the customer happy and don't want to ruin it!

I don't refrigerate my ganached cakes