Gluten-Free Rainbow Cake in the House | April, Anti-Gluten Activist

The Rainbow Connection. Cake style.

April’s Gluten-Free Rainbow Cake Experiment had some challenges – but we can all learn from her mistakes!

Article Courtesy: April Peveteaux, Gluten Is my B*tch

Nope, I can’t believe I did this either. Although when I show you the full-on photo you will see how I jacked it all up and realize that oh, yes, that seems more like April’s style. But let’s just bask in the amazingness of this gluten-free six layer rainbow cake that KICKS ASS. And actually is not that hard to throw together, believe it or not. That is, if you’re a normal person with loads of patience and realistic expectations of the hours in the day and such. But even if you’re like me and expect to whip up this masterpiece in a few hours before company comes over, it can be done. The first thing you do is head to the store and buy up all the gluten-free vanilla cake mix they have to offer.

I LOVE XO Baking Co.’s cake mixes, pancake mixes, buttercream frosting mixes—basically everything they do I am a huge fan of eating in mass quantities. Tragically, they did not have enough left at the gluten-free store so I had to use two different kinds of cake mixes. Which is fine, it’s just not as easy and I’m all about making things as easy as possible for you people (and of course, for myself.) You will need three regular gluten-free cake mixes for this recipe, or use one of your favorite cake recipes and triple that sucker. Now, let’s talk about frosting.

You can also go with three gluten-free frosting mixes from XO Baking Co., or you can triple one vanilla buttercream recipe (see below). Buttercream is so freaking good, and naturally gluten-free, but when you’re talking about this quantity you should really use a KitchenAid stand mixer. Says the girl who burned the motor out of her Cuisinart hand mixer whipping up this butter and powdered sugar magic.

Why yes I have been waiting until the last moment to discuss food coloring. Let’s all just work with the assumption that food coloring is not good for you. Apparently there are some food colorings out there that have gluten as well, though I have not yet stumbled across those vials of poison. McCormick’s food coloring is gluten-free so go forth and dye those vanilla cakes.

Now, let’s talk about how you can avoid this situation –

gluten free rainbow cake

It looks like I took that cake for a ride around Mulholland in a roadster. Much less exciting, I simply could not wait for one cake to cool before baking the next (I only have two 8″ rounds) and then started slapping that icing on way too soon. Hence, my crazy cake. So here’s what you need—it’s called patience. Always allow your cakes to cool completely. Level the top of each cake with a serrated knife, and add a crumb coating of icing to every layer and the top of the cake and allow the thin layer of icing to dry completely before you do the big final icing situation. Sure this kind of waiting means you’re hanging out with rainbow cake all day, but you get to hang out with rainbow cake all day.

Rather than be intimidated, just know this: You’re making three two-layer cakes and icing them. You simply divide these three cakes six ways, and dye each layer a different color. Sprinkles optional (but highly recommended). It really is that easy. Also note, if you allow the cakes to cool completely before leveling, icing and stacking it will look perfect. But even if you go all slap-dashery like I did, it still tastes magical.

Get your rainbow on.

Gluten-Free Rainbow Cake

Prep Time45 mins
Cook Time25 mins
Total Time1 hr 10 mins
Course: Dessert
Cuisine: American
Keyword: gluten free cake
Servings: 20 Servings
Author: April Peveteaux


  • 3 packages gluten-free vanilla cake mix and what package requires usually butter, oil, eggs, and/or milk


  • 3 packages gluten-free vanilla buttercream frosting follow instructions or use this recipe:
  • 6 sticks unsalted butter at room temperature
  • 9 cups powdered sugar sifted
  • 1 teaspoon salt
  • 4 Tablespoons Gluten Free vanilla
  • 10-12 Tablespoons milk


  • Preheat oven to 350 (or what cake package reads). Using non-stick spray, coat all of your 8″ rounds (you’ll need 6, or re-use what you have).
  • Mix cake according to directions. Divide batter equally into six different bowls. Using gluten-free food coloring, dye each bowl the following color: purple, blue, yellow, red, orange, green. Pour mixes into 8″ rounds. Bake 2 or 3 rounds at a time, and put the remaining batter into the refrigerator until it’s time to cook.
  • Allow each cake to cool completely. Prepare frosting while cakes are cooling.
  • Using a stand mixer or a very strong hand mixer (highly recommend the former), beat butter until smooth. Slowly add powdered sugar and mix thoroughly between each addition. Add salt, vanilla, and milk incrementally until frosting is the desired texture. If you want to add a crumb coating (I did not but this will make it look better) set aside 1 cup of frosting in medium bowl. Continue to add milk and mix until the frosting in the bowl is very thin. This will be your crumb coating frosting.
  • To stack and ice the cakes, place the purple round on the bottom of your cake stand or platter. Using a serrated knife, level the top of the cake. Either frost the top of the purple layer with frosting, or if you’re doing a crumb coating, add a layer of the thinned frosting and allow to dry before adding 1/4 inch of frosting. Repeat with each layer in this order: blue round, green, yellow, orange, and red.
  • After each layer has 1/4 inch of frosting, use a spatula to ice the outside and top of the cake. Smooth the edges with spatula or the edge of a knife. Add sprinkles and serve.