I am making a Batman themed cake in a couple weeks and need some help. They want a dark blue cake with silhouettes of buildings around the cake. Some of the buildings will be taller than the cake, to they stick up over the top of the cake, if that makes any sense. I plan on making them in the near future so they can dry, but am unsure if I should use straight fondant, fondant with added tylose powder, or a 50/50 fondant/gumpaste mixture for the buildings. I want them to hold their shape, and not have the tops of the buildings fall or bend. Which option would be best to use, in order to have the cutouts maintain their shape once added to the side of the cake?
If they're going to be a dark color I'd start with colored fondant and add tylose to it to make a quick "gumpaste."
Try pastillage. It dries fast, and super strong. Fondant has shortening which can make it dry slow, and can serve to weaken it. Gum paste can dry well, but should be used for thin appocations like leaves or petals.
Just find a recipe and try it out. Pastillage is meant for this kind of stuff so it is VERY strong (showpieces, etc).
Just quickly cut out your silhouette with an Xacto knife and dry it by laying it over a big tube the same size as the finished cake. Clean edges with sandpaper and color with spray color.