Boxed Cake Mix | 4-5 Tubs Icing | Gel Food Coloring | 8″ Cake Pans | Parchment Paper or Round | Icing Spatula | Piping Bags | Fondant | Skewers | Toothpicks | Gold Sprinkles | Star Sprinkles (Similar) | Black Gel Frosting | Rainbow Candles (Similar) | Gold Candles (Similar) | Rainbow Unicorn Plates | Rainbow Art Napkins | Hair Extensions
I’m usually a health-nazi when it comes to food. All-natural, organic, whole foods, etc., etc. … However, my little princess has asked for this cake several years in a row, and I finally caved. They don’t eat the cake anyway, they eat the icing, right? I mean, if any cake is worth eating junk, this is it.
Using 2 boxed (shudder, I know!) vanilla cake mixes, a package of gel food coloring (yes, really), a ton of icing, and two 8″ round cake pans, I went all in for the rainbow layer cake! I’ve never made such a fancy cake before, and may never again. With a bit of patience, this one was totally worth it! I broke the project up into a few phases to save my sanity…
Day 1 – Make 2 boxes of vanilla cake mix batter & separate into 6 parts using measuring cups (and patience). This was actually one of the most annoying steps. Add gel food coloring (for richer color) to each of the 6 parts, 1 at a time, and bake. I had 2 8″ cake pans, so I did this 2 layers at a time. Purple & Blue, Green & Yellow, then Orange & Red. I traced the cake pan onto parchment paper & cut out circles that fit into the bottom. This saved a ton of headache with cake potentially sticking to the pan and also helped separate the laters while waiting for Day 2. My layers baked a bit quicker than the box suggested (since I was making 3 layers, I’m sure) so watch them. I stuck my layers in the fridge and went on with life for the day…
Day 2 – Assembly! Put down the purple layer – ice, blue layer – ice, etc. until all layers are assembled. My icing was hard-is since the weather was cold, so I zapped it in the microwave for a few seconds before spreading. Then do a crumb coating. That’s where you do a sloppy layer of icing covering the entire cake to contain the crumbs. It doesn’t need to be pretty. Back in the refrigerator to harden! I used 2 tubs of store-bought icing for this.
I also used store-bought fondant to create the ears & horn, then put them in the refrigerator to harden. A few things I learned about fondant: It’s basically play-doh. If you get it wet it becomes sticky – useful if you need to stick, say, 2 cone-ish logs together to swirl around a skewer into a twisty horn. Also for forming the bottom of ears onto toothpicks.
Day 3 – Pretty Icing! I used another 2 tubs of icing for this step, 3 would have been better. I put a pretty coat of white icing all over the cake. I wet the fondant horn and middle sections of the ears, then sprinkled gold springs on. I split the remaining icing into 6 sections and 1 at a time mixed in gel food coloring, then using a piping bag, started forming the mane. I started with the purple (the end of the rainbow) and worked my way up. This drew a crowd and I had some BIG, excited eyes watching! The eyes were drawn on with gel frosting and I added star sprinkles for a finishing touch.
With some patience and planning YOU CAN DO THIS! I usually make from scratch with the best organic ingredients, but that may have been too much for this amateur baker. The store-bought cake & icing saves a ton of time and effort making this totally do-able!
Plus, kid’s birthday parties have gotten utterly out-of-control these days. What ever happened to the art of the homemade cake? It may not be for every year, but do it when you can! Oh, and how about the rainbow french braid made from clip-in extensions? Her friends went nuts over it!