Skip to Content

This post may contain affiliate links. Please read my disclosure policy

How to Make a Rainbow Unicorn Cake

Sharing is caring!

It’s time to make another delicious birthday cake! This time it’s a Unicorn Cake!

Unicorn Cake

Believe it or not, but our Junior Gizmo gal just turned 13! Yep, we have a teenager in the house! (Yes, if you are wondering, I’m still in denial.)

Pink birthday

Each year, I make my kids a special homemade cake for their birthday and this year was no different. I’ve made everything from Batman to Barbie to soccer ball and Elmo cakes but I have never made a rainbow cake. Or a UNICORN cake for that matter!

Until this year.

Savannah is obsessed with unicorns and everything pink right now so I decided this was the year of the unicorn cake.

pink birthday

My first idea was to just make a unicorn cake, because let’s be honest, that seemed like a big enough project on its own. Then I thought, instead of just a funfetti cake (my original idea), a rainbow cake would make the most spectacular cake on the inside. Sure, it’s a little more work but after seeing how it turned out, it was totally worth it.

Plus, I cheated and used two boxed cake mixes instead of a homemade cake recipe. And you know what? I’m completely okay with that. I’m owning it. I can’t really tell the difference between boxed cake mixes and homemade so I decided to put the effort into the homemade buttercream frosting and the unicorn cake design.

While this entire cake can be made in an afternoon, I decided to split it up into two days. I wanted to freeze the rainbow cake layers to make the frosting process that much easier and it worked out great.

To be honest with you, the hardest part of the cake was getting the unicorn eyes right. It’s not easy working with black frosting gel on a white frosting. One wrong move and it’s over. It’s not easy to fix black frosting on top of white without making a mess of it all.

Surprisingly, the unicorn horn and ears were fairly simple to make with a little store-bought fondant and some Wilton Gold Edible Spray.

I put the cake making process into a video for you to show you just how easy it is to make this cake but let’s start with the ingredients.

unicorn cake

RAINBOW CAKE Ingredients:
2 (two) vanilla or white cake mixes (ingredients listed on box – eggs, water, oil)

Make two (2) vanilla or white cake mixes according to box. Divide into 6 bowls. Add food coloring to each bowl (each bowl a color of the rainbow). Pour batter into 6 round 8″ pans. Bake at 350 degrees for 15 minutes. Cool completely.

2 sticks butter
4 cups powdered sugar
2 teaspoons vanilla
2 tablespoons milk
Rainbow Food Coloring (red, orange, yellow, blue, green and purple)

Blend all ingredients together. That’s it. Add rainbow food coloring to make it different colors.

UNICORN CAKE Ingredients:
Wilton Gold Color Mist Spray
Sucker Sticks (or wood rods)

Make the buttercream frosting according to recipe above. Make unicorn horn, ears and assemble cake according to video. 🙂

That’s it. The Rainbow Unicorn Cake turned out fantastic. Dare I say that it was one of my best birthday cake creations? Here’s another birthday cake option – Funfetti Birthday Cake

This site uses Akismet to reduce spam. Learn how your comment data is processed.

Julie Perkins

Sunday 11th of February 2018

Repeat after me:

I will NOT wear sunglasses on my head indoors anymore...

This site uses Akismet to reduce spam. Learn how your comment data is processed.