Actually there is a way to color chocolate without actually adding dye to it. I know that moisture is a huge detriment to chocolateering, so adding gel is pretty risky to begin with. There are actually some cocoa butter sprays which I have used before. I used green ones for leaves, but I`m sure that you could find all sorts of colors. It`s just like spray painting chocolate, only it is edible. I`m pretty sure Wilton makes them. You might have to order it because I don`t think stores would carry it unless they have a good cake decorating section. Personally I would not spray the pocky, but it might come in handy for the helmet.
I`m not too sure if they would make chocolate melts in the deep blue that Benny has, and adding in more coloring could help get it out of a pastel color, but it still might not get it quite dark enough.
Edit: Note on chocolateering: Just realized you were using white chocolate. Instead of melts, you might just want to use white chocolate chips or bar chcoclate that was not altered for quick melting. White chocolate by itself can call for adding a little water to get it to melt. I haven't tried dying it before, so I'm not sure if it would work fabulously, but it might help to add dye to it. Of course that would mean you would have to temper it properly which means you'd need a good thermometer and it could be more of a hassel...
Also, that filling sounds really good. What kind of cake was it? White or yellow?
I have yet to work with rhubarb, really, so that flavor is still new to me.
Second edit: Okay, after a few searches, Wilton's product is called Color Mist. Actually I kinda want to pick up some for my very late birthday cake I wanted to make. Anyway, it doesn't look like they make dark blue color mist, just sky blue. However, I did see some search results for dark blue color melts which appear to be the correct hue for Benny. So, I would try to find those, though I'm not sure what stores would carry them.
Edited by Unikitty Tekulo, Apr 02 2014 - 07:17 PM.