We’ve made these bento boxes a couple of weeks ago. The request were very clear, that we could not use any artificial food coloring. While I also try to avoid using food coloring, but I have to admit that it’s easier to use them since they’re cheap and available in almost any colors you want. Luckily that the kyaraben was Lightning McQueen from one of the bento I’ve made several months ago.
Those colors were relatively easy to make; I used egg yolk for yellow, egg white for white, soy sauce for brown, and red pepper juice for red. The red was quite tricky since I had to mix it with cornstarch (unless the egg sheet was too fragile to be cut properly) so the red was slightly lighter and almost become pink, not deep red like the real Lightning McQueen.
All of those egg sheets were made, cut, and assembled a day before delivery day so on the D-day all the preparation was ready. We only need to cook all the foods and arrange them into the boxes. The only thing that took quite some time was assembling those tiny orange (carrot) square but we managed to finish them all way before schedule.