Baking Rainbow Cakes in a Jar

A friend posted this recipe on facebook on how to bake cakes in Mason Jars. I decided to give it a go and give them the full rainbow treatment that the recipe suggests.
As I knew the dying of the icing and the filling of the jars would be time consuming I opted to cut some corners by using box cake mix and ready made icing...I know this goes against everything I believe in, but sometimes you just gotta go for expediency over principles. I'm sure they would taste better if I had made my own cake batter, but the primary gimmick is the appearance here anyway.

The first challenge is working out how to split a large amount of cake batter into 6 equal portions.

Here's how I did it - a digital scale that you can zero will be your friend.

1. Weigh your empty mixing bowl - mine was 1 lb 9oz
2. Weigh your mixing bowl full of batter - 5 lb 15 oz
3. Total weight of batter = 5lb 15oz minus 1 lb 9 oz = 4lbs 6oz
4. Six equal portions of batter will be 4 lb 6 oz divided by 6 which is 11.6 oz
5. Put your empty bowl on the scales and add 11.6 oz of batter...repeat until all 6 bowls are filled.

First lesson learned - The math would have been easier and more accurate if I had used Grams and Kilos rather than pounds and ounces. A gram is a smaller unit than an ounce so you get a more accurate reading...also, the smallest unit my scale would read is 1/8 oz. Working out what 11.6oz was (11 and 6 tenths) when you can only measure in 8ths was a challenge. I went with 11 and 5/8 to approximate.

Next I needed to color all 6 batters.

Gel food coloring is preferable to liquid as it won't change the consistency of your batter that much. I bought a pack of 4 colors - red, yellow, green and blue because I figured I could mix orange and purple to get the 6 colors I needed. As you can see from the picture this was only partially successful.

Orange was not difficult to mix, but I found getting the red an intense enough color took a lot of gel and I was concerned about having enough left to mix the purple. Little did I realize that mixing purple would be the bane of my existence!

Second Lesson Learned  - I bought the 4 color pack to save money. I could have bought each of the colors already mixed in gel form. My red would have probably been more intense if I'd done this and my purple might have actually looked purple. If you are not confident in your color mixing skills buy them ready mixed.The colors looked muted after baking (see pics below) so the more intense they are at this stage the better.

The next stage is filling the jars with the 6 layers. I was concerned about how I could split the batter. evenly among the 6 containers so I resorted to math again.

1. I have 11.6 oz of each color cake batter
2. 11.6 divided by 6 is approximately 1 and 7/8 oz in each jar.

I placed the empty jar on the scales and zeroed them. Then I drizzled in the first color from a spoon and when I reached the correct weight stopped. Then I zeroed the scales again and added the next layer. Continue adding and zeroing until all 6 colors are in the jar.

The recipe said to fill the jars 3/4 full. Mine were slightly fuller than that and I had a little batter left over. I knew from the recipe that they would rise to a domed top and I would have to cut some off the top before icing so I wasn't too worried.

After 40 minutes in the oven I was greeted by this.

Third Lesson Learned - 3/4 means 3/4. My division of the batter was even, but it was still too much for the size of the jar. The tray of water that the glasses stands in catches any mess, but I did have some dribble down the side of the glasses and some batter wasted. I think if I'd been a little less liberal with my filling I might have stretched the recipe to fill 7 jars rather than 6. It's not a huge deal as I have to cut off the tops anyway, but an extra jar might have been nice.

The trimming of the cakes once they had cooled was a relatively simple affair. It's helpful to have someone else with you so that you don't gorge on all the spare cake yourself.

Icing them is a simple task.

Now all I have to do is put the lids on, stick some circular labels in the lids and maybe tie a few ribbons for added fun.

Fourth Lesson Learned - The leftover cake that I cut off goes really well with the leftover icing :)