Hello! So I've been trying to put chocolate ganache into a filling for a cupcake. They are good and creamy at first but the chocolate eventually sets up. Am I doing something wrong?
Thanks!

Add as little more cream, so it keeps a softer consistency.

Are you whipping it?

I always whip my ganache when using it for filling in cake or cupcakes.

ganache ratios
for bitter or semi sweet chocolate...equal parts choc. to cream
for white or milk 2 parts choc to 1 part cream
sometimes a add a little butter to make it smoother, other options is to use 2 parts choc. to 1 part butter, this is rich and smooth but will get hard if chilled. i agree that whipping is nice to add a lightness to it.