Two-Tier Rainbow Striped Mini Cake!

rainbow cake white background

I’ve made quite a few bright and colorful cakes recently. That made me wonder: Am I in my “rainbow” period? Am I like Picasso? Probably not. I’m just doing my best to squeeze all the summer I can into my decorating before it’s over. I’m sure you know by now that I love stripes. Plus, Cyndi Lauper stopped by my imagination and reminded me that she can see my true colors shining through, and that’s why she loves me!

full rainbow cake slanted view

This cake is another super tiny one. 🙂 I know the two tiers make it look bigger, but the bottom tier is just four inches in diameter. It’s so small that although I originally wanted to put all seven colors of the rainbow, I could only fit five!

rainbow cake close up drip

The top is decorated with some white chocolate ganache, Wilton rainbow sprinkles, and some Rafaello almond coconut balls. I so plan to use these closer to Christmas too. If you’re excited to learn how to decorate this super easy cake, keep reading!

rainbow cake buttercream colors

The first step is to divide your buttercream into several bowls and color it. I like using gel food color for this since it’s super concentrated and is much brighter than liquid colors.

adding rainbow stripes bottom tier

Next all you have to do is place each color in a piping bag (or a heavy duty sandwich bag) and pipe rows all the way around the cake. A turntable works wonders for this.


Make sure that the top color extends above the top of the cake, that way you can use your spatula to bring it towards the center, covering the top. Ignore the dinglehopper, Ariel. I’m not even sure what I used that for anymore.

smoothed out bottom tier rainbow cake

Here’s what the stripes look like when you use a bench scraper to slowly scrape around the side. Keep the scraper level to your cake board and slowly make your way around, removing the excess buttercream every time you do. If you see any air pockets you can simply fill them in with new buttercream and go around again.

top tier smoothed out

Do the same for your top tier!


Since this cake was so small I didn’t even bother putting in any dowels or straws. However, if you plan to make a larger cake you will definitely need to add some structural support. The easiest way to stack them is by first popping them in the freezer for ten minutes. The buttercream will firm up, making it super easy for you to just pick up smaller cake and plop it on top of the larger one.

two tier rainbow cake stacked


The next step is to add your white chocolate ganache. The ratio for this is three parts white chocolate to one part cream. I like to go by weight. For a cake this small I used 90 grams of chocolate and 30 grams of cream. Let it sit for 5-10 minutes to thicken, then transfer it to a piping bag and add your drips all around the cake.

two-tier rainbow cake with white chocolate ganache


The last step is to add your decorations! The raffaellos and sprinkles should not have any problem sticking to the ganache. If you notice, I cut one in half to add some height differential.

rainbow striped caked adding sprinkles

Here’s the view from the top. 

finished rainbow cake brick background

In the end, I’d say she’s a beaut’. So when it comes to colors, don’t be afraid to let them show.

Your true colors.

True colors.

Are beautiful, like a raiiiinbowwww.

Until next time <3

Rainbow drip cake pinterest graphic

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