I need to make a US postal delivery truck to go on a cake for Saturday. It will be a side view of the truck so it is flat. Do you think if I did this in color flow or royal icing tomorrow, it would dry in time? Which would be better to use? Ive done color flow in the Wilton course, would royal icing work the same way?
Or, should I offer to make it in fondant? That would be easy to cut out!
Color flow is re-inforced royal. It really can't be cut. It has to be removed in order to cut the cake. Royal can "sort of" be cut, if it's thin enough (but if it's on the cake too long, it can soak up grease and that looks kind of funky at times), but it still fractures. Both will dry by Sat. if it isn't super humid. Put test dots the same thickness as the piece on the side of the wax/parchment and pick one up every day or so. It's dry when you can't press into the dot.
My preference would be a buttercream transfer, a chocolate transfer, or fondant. The chocolate can usually be cut with a warm knife, if it's thin enough, too.