I froze a trifle years ago but it was a failure, as the milk separated. There is a milk (forget the name of it) that you can freeze, which I think would do Ok in a trifle. The rest of it was OK. I used to do a pudding where I used suet (the light variety) and make it like a dumpling only sweet, and bake it - that was nice, but a bit crispy on the outside. My children used to call them 'rocks' but they vanished quickly. Rarely do puds these days for health reasons (husband's more than mine) so we stick to low fat youghurt except on Sundays.