Rainbow Cake

No... this is not an original idea. 

Yes... it's super easy!

Yes... I'll be making it again! 

I found a recipe on MarthaStewart.com.
I was going for the same look as she had but didn't have the time or energy to make it from scratch like she did and I was not comfortable with putting in the amount of food coloring required to get the vibrancy of colors that she did.
So I made it work with what I had and here's what I ended up with...

I used two boxes of white cake mix and two containers of white frosting.

"Gasp! You mean this isn't made from scratch with your own freshly milled grain?!"

Nope.
I work hard to feed my family healthy, nutritional meals regularly so I don't mind a processed splurge every so often. Otherwise, what's the fun?

Anyway...
two boxes of white cake mix
two containers of white frosting {one of ours was FunFetti}
food coloring
as many cake pans as you can gather
butter and flour/PAM/coconut oil or some other means of greasing your pan

I made up both boxes of cake mix and divided the batter evenly into six bowls {approx 2 cups of batter for each bowl}. One by one, I used the food coloring to dye the batter red, orange {red and yellow}, yellow, green, blue, and purple {red and blue}.
The colors didn't look quite right, especially the red and orange but they all intensified during baking. The red was more of a dark pink, the purple was a lavendar, and the yellow looked nearly white before baking.
Grease the pans well... I used butter and flour... and bake each pan for 15 minutes. Test with a knife/toothpick/spaghetti noodle for doneness.

Once done, let cool for 10 minutes in the pan, then turn out onto a cooling rack and let it cool for another fifteen or more minutes.
Once FULLY COOL, use a long knife, such as a bread knife to cup the tops of the cake level.

{We gave the tops to Mak to eat at her leisure.  What can I say, it was her birthday!}

You may notice that the outside of your cake is slightly browned like mine...

Once the cake is frosted, you will not see these edges, just the great colors you've mixed!
I put a VERY thin layer of frosting in between each color. Just enough to make the pieces stick.
It took me one container of frosting to put between the layers then I loosely covered it in plastic wrap and put it in the fridge for 30 minutes. I figured the cake would cut a little easier, be less crumbly, and show the colors better if it was a bit cool.

Then I used one container of frosting for the outside.
I probably could have used one more container but that just sounded CUH-RAZE-EE!
Then I topped it off with some "FunFetti", a quick and cheezy little banner...

really?!...
"Yay Mak!"?
I'm sure I could have come up with better than that!

Anyway... here it is!

or maybe more like "there it went"...

Delicious, fun to look at, and fun to eat!