Every year around Christmas, my daughter and I make su gar cookies with a hard glaze, and paint all sorts of things on them. It's a lot of fun, we always make a mess and have a great time!

I've never been satisfied with the food coloring/paintbrush combo, as the food coloring is pretty runny and hard to work with. This year, I was looking at a package of markers, and noticed the "Non-toxic" mark on the back, and got to thinking . . . and eventually this instructable was born!

Step 1: Gather Materials

Update 3-9-14 -- Thanks to instructabler Conrad3000 for pointing this out, you can buy unfilled markers from Crayola! Saves some steps, that's for sure! I'm retiring my original set this year, so I'll give them a try. He mentions he's also trying them with Crayola's airbrush kit, I may end up trying that as well.

This is a very simple project. For you need only two things:

A package of non-toxic washable markers
Food coloring

For the markers, I went with Crayola brand, only because they are a name I'm familiar with, and I suspect if people had a problem with toxicity from their products it would be big news. It's not like a huge amount of anything from the marker itself is going to get into the food product, but it's better safe than sorry.

I got food coloring from the dollar store--you can pay 5-6 bucks at a regular store but I think this will do. As near as I could tell comparing it to the stuff I bought from Albertson's, it's exactly identical.

As to tools, you'll need:

Several small glasses (like shot glasses)
Eyedropper
Lots of paper towels
A surface that's either protected or you don't mind staining
Pliers
Watertight jar
Toothpicks
Plain white paper
A heat gun or hair dryer

Step 2: Clean the Markers

First you need to remove the old ink from the markers. Pop the back end off of each marker--I had to use pliers, and a heat gun to soften the plastic. Inside you'll find a piece of felt wrapped in plastic that sits on top of the felt pen tip, saturated with ink.

Next, drop each part of the disassembled marker (cap, back, main body, ink cartridge) into a watertight jar. Fill it with water and shake, dump out, and refill. Do this a couple of times, then let the markers sit in water for a while. I ended up doing this five or six times over the course of a couple of days, until I was satisfied the ink was totally drained.

Finally, set the now clean parts out to dry. If you're able, set them in the sun for a couple of days, until you can squeeze the ink pack and no liquid comes out.

Step 3: Refill With Food Coloring

There are two tricky parts to this step--mixing the colors properly, and not overfilling.

It turns out that liquid red food coloring, at least the dollar store stuff I had and the McCormick stuff I got from Albertson's both have a very slight orange tinge to them. This made mixing a number of the colors I wanted tricky or downright impossible! Grey, pink, purple, and black were all very difficult to attain, and most of those ended up with a slight greenish cast to them that was impossible to get rid of.

I recommend using the mixing chart on the back of the food coloring package as a starting point. Use a toothpick to test the results on a sheet of paper, and then add more colors as required.

Once your colors are ready, use an eyedropper to put a couple of drops into the main part of the pen, so it can start to soak into the felt. Next, start dripping the food coloring into the felt ink cartridge. You should see it start to bleed through the felt. Stop when it's completely full, don't let it fill up so much that it starts to drip out the other end. If it does, use a corner of the paper towel to soak up the excess color.

When that's done, drop the ink cartridge into the pen and seal it back up. Dip the tip of the pen into the food coloring and then dab off the extra. Finally, put the cap on and let it sit for a while. Check it again and see if you need to soak up any more excess food coloring.

Repeat until all you pens are done.

Step 4: Color Your Cookies!

This should work with any reasonably solid food, but as I said, we used it for our painted sug ar cookies. Be careful not to push too hard when coloring, and be creative!

Step 5: Final Thoughts

This was a pretty fun and simple project! India and I had some extra fun with the cookies this year, as the pens made detail work a lot easier than when using paintbrushes.

I'd really appreciate any thoughts and feedback you have on my instructable. Take a minute to rate, subscribe, and comment!

If you should happen to make your own food coloring pens, or your own painted sugar cookies, post an image of the food you colored in the comments below and I'll send you a patch!