Rainbow Cake Tutorial

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I love throwing parties for my kids.  I love planning out the theme and decorations and treats!  When my daughter told me she wanted a My Little Pony birthday, my mind went into overdrive imagining what I could do with it.  Since her favorite pony is Rainbow Dash, we decided to go with a rainbow theme.  And with a rainbow theme, you need a Rainbow Cake.

When I first saw this type of cake, I was in awe.  How amazing and colorful!  I promised my daughter I would make one.  And then I got a sinking feeling in my stomach. What had I just gotten myself into?  I knew I had to deliver in a big way.  I have done homemade cupcakes and cakes before at my daughter’s  Superhero Party, Princess Party and my son’s First Birthday.   But this one just seemed very daunting.  It is not.  It just takes a bit more time.

Here is how to make your Rainbow Party amazing…..

3 boxes White Cake mix 
{yes, boxed mix. I’m trying to save time here}
White Icing
Food Coloring
9-inch cake pans
Wooden Dowels

Mix your cake batter as directed on the box. 

Divide the batter equally into 6 bowls.

Add food coloring to each bowl and mix well.  If you look on the back of the food coloring box, it tells you how many drops of each color you will need.

Pour the batter into your pans and bake according to directions on the box.  It helps if you have 6 cake pans.  You will be finished in no time.  I had 2 so it took a bit longer.

After the cake is done baking, let it cool and then remove from the pans and place on a wire rack to cool completely.

When completely cool, cut the domes off of your cake layers.  You will need the layers to lay flat on top of each other.

Place the purple layer onto whatever you plan to serve the cake on.  I use cake circles.

Place a dollop of icing in the middle and spread out to the edges.  You should probably put a bit more on than in this picture.  

Place the blue layer on top of the purple and repeat the process.  Keep alternating cake and frosting until you get to the red layer.  Do not frost the top of the red layer.

Place 3 dowels into the middle of the cake.  You do not want your masterpiece to topple over after all your hard work. Be sure to place them in the center because when you slice into the cake, you don’t want a dowel in the middle of your piece.

Next, you are going to want to put a crumb coat on the cake.  This is essential and it is the key to getting your final layer of frosting smooth and crumb free. A crumb coat is basically a coat of thinned frosting and it adheres the crumbs to the cake so they do not mess up your final coat of frosting.  Think of it as a primer for a cake!

This is how it will look after the crumb coat.  Do not worry. This will be covered up.

Put your cake in the fridge until the crumb coat hardens a bit.  

Remove your cake from the fridge and frost.

I am not the best cake froster by a long shot.  I do not have fancy frosting tools.  You can get a smooth coat by having the proper tools but I was just thrilled with having no crumbs in my final coat.  

I added Rainbow Dash and some rainbow candy to the top of the cake.  I wanted to keep it simple on the outside because the inside is so spectacular.

Note to self…the bowling alley does not provide the most aesthetically pleasing backdrop. 

My daughter was so excited for me to cut the cake at her party.  Her friends were ooh-ing and aah-ing.  Their reactions were priceless.

This cake will really make a statement at your party. Better get yourself a piece.  It goes quick.

 What is your favorite cake that you have made?


  1. Kelly this cake is beautiful! I bet it’s tasty too, but it’s just so pretty to look at!! I pinned it:)

  2. Love this!! As the mom of four girls, surely a rainbow cake will be in order at some point. I also laughed out loud at your “note to self” about the bowling alley. 🙂

    HH at harvardhomemaker.com

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