Well, that usually depends on what kind of frosting you want. There are some with simple tastes that can be made in less than ten minutes, or a few complex ones that can take up to twenty or longer depending on the equipment or ingredients you might have...ah, but time hopefully won't be too much of an issue for us--once the cake layers have been baked, they'll still need a little more time to cool afterward before we'll be able to add the frosting to it.

[So...yeah, we should theoretically have enough time to make our own frosting for this?]