I mean soft, spready icing, not Christmas cake icing.
It needs to be white in colour.
I need something you can happily eat a lot of (multiple cake layers all sandwiched together, plus more over the whole cake).
If I make it with butter it will be a creamy colour, not white.
I have made this icing before but I can't remember if it was white or cream coloured. I do remember it was delicious though.
I am reluctant to use vegetable shortening or cream cheese icing because I think that too much of either of those is not nice.