Original recipe yields 1 servings
This is really a recipe for artists - the trick is to paint very thinly. No wonder there are negative reviews! Egg tempera is an ancient technique used for creating exceptionally brilliant colors, and it just doesn't work when the colors are plastered on. It's not a technique that kids can handle very well, and even adults have trouble keeping the layers very very thin. You might want to add the "paint in very thin washes" instruction.
After reading the negative reviews (smells/tastes bad) I was almost scared away from trying. But I was disperate for a quick decorating trick. This worked great - NO BAD SMELL, and TASTES great. One recipe makes enough to decorate 60+ cookies. I mixed the egg and water and then separated it into 5 small bowls to add desired color(s). It brushed on easily (I don't know how you could make it too thick, it is a very thin wash). I then added colored sprinkles/colored sugar and baked. The result was quick and pretty cookies that tasted great too. I baked the cookies on parchment paper, I used one sheet for all the cookies - no stains or any problems like others complained of. Definitely recommend for kids of all ages. This would also be great to use as a base and then add piped icing designs after the cookies are baked.
I gave the kids (ages 4 to 10) egg yolks and water. They mixed them and divided them among cups in an ice tray. They made their own colors and painted the cookies. It was much easier than icing the cookies, and they loved their artwork. The colors change a little when baked, but not too much. A definite "keeper".