A sprinkle-coated colorful cake makes a beautiful centerpiece dessert for a party. Learn how to decorate a rainbow cake like a pro with my easy-to-follow tutorial.
Rainbow cakes make me so happy, and it was one of my favorite designs to make with my home bakery. I actually started making them because I agreed to donate a cake to a silent auction for a local organization, and one of the ladies posted a pinterest picture of a layered rainbow cake. I offered to make it, but I knew I couldn’t just frost it in white, I had to make it special! The cake needed to be something fabulous and fun on the outside as well as the inside, so I covered it in sprinkles and piped little frosting stars up top. It was beautiful and did so well at the auction I had 3 additional cakes ordered the week after for future events, and the rainbow cake – decorated as pictured – became a Goodie Godmother signature. Now I’m going to show you how to decorate a rainbow cake so you can make one at home!
The bakery is no more, so this cake is now on the blog. That way, we can all make pretty rainbow cakes to celebrate special occasions!
How to Decorate a Rainbow Cake: Creating the Cake Layers
I used my yellow cake recipe for the cake layers, divided the batter in 6 equal portions (a digital kitchen scale really comes in handy here), and colored with gel food coloring.
To get the correct quantity of batter for each layer of cake, weigh your bowl and mixed batter, subtract the weight of the empty bowl, and divide by 6. If you are mixing your cake in the standard 5-quart KitchenAid mixer bowl, the metal bowl weighs 29 ounces. When mixing in a standard mixing bowl using a hand mixer or another model of stand mixer, weigh the bowl before you start baking your cake.
If you have 6 6″ round cake pans, you can bake the layers all at once, but I don’t, I have two, so I bake the layers two at a time. The yellow cake recipe layers bake in about 18-20 minutes for this cake. Once the cake layers are baked and cooled, use a cake level or serrated knife to trim any domed tops. Make the extras into cake “sandwiches” with spare frosting. Other humans of all ages will love you.
How to Decorate a Rainbow Cake: Frosting and Adding the Sprinkle Coating
Use Swiss meringue buttercream, or your favorite not-crusting buttercream as frosting. If you use a crusting buttercream, have your sprinkles and everything ready so you finish decorating the cake before the frosting crusts, otherwise the sprinkles won’t stick as nicely.
Let us now step into my “office” to watch the video tutorial to explain how I cover the cake in sprinkles to get the best results…
I hope you enjoyed my tutorial on how to decorate a rainbow cake!
Don’t forget to pin for later…
Friday 26th of October 2018
This is wonderful. Would it work with log shapes sprinkles?
Mary (The Goodie Godmother)
Friday 2nd of November 2018
Yes, but you may have to do a little more patching to get a solid covering. :)
Sunday 6th of March 2016
The inside of that is amazing beautiful, Mary!! No wonder it's your signature ;)
Monday 7th of March 2016
Thank you! :)
Paige @ Where Latin Meets Lagniappe
Friday 4th of March 2016
So beautiful Mary! You always totally AMAZE me with your talent :) I love the rainbow sprinkles (and my kids would be die hard fans!)
Monday 29th of February 2016
Ok. First of all, loved the video. Second, you have way more patience than I. Gently glide your hand up without touching the cake and let the sprinkles fall onto the cake? Me? I'd be throwing those sprinkles onto the cake like there was no tomorrow. And you would have been right. I would have found sprinkles all over my kitchen for years to come.
Whitney @ That Square Plate
Monday 29th of February 2016
Loved that you made a video how-to! It looks so much easier than I thought it would. I'm such a fan of sprinkles and this cake is absolutely beautiful!! (Very cool charity too!)