We recently celebrated my children’s birthdays in one combined sibling birthday party and decided on a Dreamworks Trolls inspired theme which included a bright, bold, rainbow color scheme and an even bolder rainbow cake!
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One of the highlights at all of the parties in our family is the cake, and believe it or not, cake decorating is my husband’s hidden talent. This time, due to his hectic work schedule, it was a joint effort and I baked the cakes while he did the decorating.
We searched Pinterest for ideas and inspiration for our rainbow cake and decided that we just HAD to attempt a six layer cake – one for each color of the rainbow!
I used Wilton concentrated gel food coloring to get the bright, vibrant colors in both the cake and the buttercream frosting.
After preparing the cake batter, I separated it into six bowls of roughly 1 1/2 cups of batter each and then added the food coloring gel and mixed by hand. I baked two layers at a time and then wrapped them in waxed paper and plastic wrap and froze them until my husband was ready to decorate.
I would love to be able to share the buttercream recipe with you as well, but it’s my husband’s secret recipe. And it’s really only a secret because he doesn’t use one – he just throws a bunch of stuff into the mixer and it turns out incredible every time!
Thankfully you can find awesome recipes with tutorials at www.mycakeschool.com!
Here is one for the vanilla buttercream which we colored with the same gel food coloring.
Here is one for the chocolate ganache that we drizzled around the top of the cake.
I was lucky enough to find the Poppy & Branch marshmallow pops at the dollar store to use as cake toppers but unfortunately haven’t been able to find them for sale online anywhere to share with you.
As for the decorating itself, I’m going to make it sound much more simple than it actually is because my husband made it look a lot easier than it was. After stacking the individual cakes in the right order, he filled them and did a crumb coat with plain white buttercream. Then he mixed the buttercream into the six different colors. Next, he piped a stripe of each color around the cake in the same order that the cakes were stacked. Using a dough scraper along the side, he rotated the cake on the turntable to blend the colors together. The top was covered in a layer of rainbow sprinkles with chocolate ganache drizzled around the top edge.
The result was a bright, colorful, rainbow cake that was beautiful inside and out!
- 6 Eggs
- 3 cups Sugar
- 1 cup Butter
- 2 cups Milk
- 4 cups Flour
- 2 tbsp Baking Powder
- 2 tsp Vanilla Extract
- Gel Food Coloring (Optional)
- Preheat oven to 350 F
- Line two 9" round cake pans with parchment paper (If doing 6 different colored layers you will need to repeat 3 times)
- Cream the butter and sugar until light and fluffy
- Add the vanilla and then the eggs one at a time until blended
- Mix the baking powder and flour together and then fold into the mixture in three parts, alternating with the milk.
- Mix only until combined
- *If doing 6 different colored layers then separate the batter into 6 equal parts (approx. 1½ cups of batter per layer) and add food coloring to each one.
- Bake for 20 - 25 minutes or until top of cake springs back when touched.