I am pretty new to decorating and am making my daughter's birthday cake for Sunday - can I fill my cake today and freeze it? My fillings will be a chocolate ganache in one cake and a custard in the other.
When did you bake the cakes?
Usually custard does not freeze well, but the ganach will be fine. Since you need them for Sunday, if they were baked today there is no need to fz them. They should be fine well covered in the frig. I don't usually recommend frig'ing cake but with the weather getting sooooo warm it might be a good idea.