How to Bake a Perfect Rainbow Layer Cake

There are a few super basic tips to baking a successful rainbow cake. If you want to know how to bake a rainbow layer cake, this is the post for you because a couple of baking tips for this makes all the difference. I tried to do this a few years ago and let’s just say, it was a fail. I have tried a few different things to improve the process and came up with a total win for this rainbow layer cake I baked for a party over the weekend. I am excited to share the tips with you so you can also create a successful rainbow layer cake.

To make the cake layers you will need a box mix for each one. There are seven colors in the rainbow but since indigo and violet seem so close, I added pink for my seventh layer. Also needed will be food coloring in the seven colors. I recommend Liqua-Gel food coloring. You can get it on Amazon! Whip up each batch of batter (a whole box mix) adding color. Bake your cake layers one a time in a 9 x 13 inch pan. I used a nonstick aluminum pan.

IMPORTANT TIP:

Grease baking pan completely so layer will fall right out.
Use GOOD HIGH QUALITY food coloring.

IMPORTANT TIPS:

Make one layer at a time, in order of the rainbow.
While one layer is cooling, prepare and put the next layer in the oven.
If a layer comes out crumbly, DO NOT use it.

If you have two ovens, you can bake two at a time. Just be sure they are both completely COOL before proceeding to the next step.

Once the first layer is cool, flip it onto a cooling rack then flip the cooling rack on to your cake base surface. You will NOT want to move the cake once that second layer gets added. Put LARGE clumps of white buttercream frosting on the corners and smaller clumps around the top of the layer.

IMPORTANT TIP:

For a perfect rainbow layer cake, DO NOT SPREAD the frosting. Spreading it can disrupt the cake layer. It will also put a white stripe in your final cake.

Add a layer at a time following these directions until you reach your top layer. Refrigerator your cake for at least 2 hours before frosting. The frosting might be squishing out of the corners. That is okay. It is keeping the layers of the cake balanced and even.

IMPORTANT TIP:

Refrigerating your cake will help it settle and prepare it for frosting.
If you cake is appearing lopsided, put a piece of parchment paper on the top and a book or two on the part that is too high to balance it back down.

Once the cake is chilled, frost it with white buttercream icing. If you are not sure how to frost a cake, I recommend you google it and watch a few videos! Decorate the top of the cake as desired. This one was for a post wedding party so I decorate it with a bride and groom toy topper set.