So the big Number 5 birthday party was fast approaching and the all important cake discussions had begun. We had gotten to the point of trying to figure out how to combine Frozen, Minions, Paw Patrol and the Little Mermaid into something that didn’t resemble Frankensteins monster (I was imagining a yellow mermaid with paws who could freeze things… not good), when Pinterest came to my rescue. Scrolling through for party theme ideas I came across a few photos of Rainbow Cakes. Looked pretty straight forward I thought, and what 5 year old doesn’t love a rainbow?
First things first – this isn’t really as much a recipe as it is cake instructions. The reason I say this is that I used packaged cake mix and frosting. And I am glad I did! This is a bit of a time consuming process so it helped to not be measuring all the ingredients as well. So here are the instructions:
- 2 x boxed cake mix (I used Betty Crocker Vanilla mix)
- 2 x 450gm (ish) containers Vanilla frosting (again Betty Crocker branded worked well)
- 3 x round cake tins (the ones I used were 22cm but if you have a different size that wouldn’t be a major problem, just make sure they are the same size and you may need to adjust your cooking time)
- 3 x bowls for mixing colours
- Food colouring (I used Queen Rainbow food colours which worked but did need a lot, I have since read gel colours work really well)
Preheat the oven as per the cake mixture instructions and line the tins with baking paper.
Make up the first box of cake mixture as per the instructions on the box. Split the mixture evenly between the 3 bowls (I actually tried weighing the mixture and working out how much each 3rd should weigh – probably just as easy to do by sight).
Now to mix up the first 3 colours. I started with purple, blue and green. Warning – it did take quite a bit of colouring to get the vibrant colours I wanted!
Put each colour into a tin and bake until cooked through (springy to touch) and has slight colour (aside from the dyed colour!). This took approx 15-20 mins but keep an eye on it as it may depend on your oven.
When cooked, let them cool in the tin for a little bit then turn out onto a wire rack to cool.
While these are baking – mix up the next box and cake mix and repeat for colours red, orange and yellow.
When all 6 cake layers have cooled, trim the top off each layer (except the red layer as it’s the top) so they are flat. I then placed baking paper between each layer and chilled the cake. This just helps with spreading the frosting so it doesn’t pick up too many crumbs. I was able to place mine in the freezer so if you can this helps heaps.
Constructing the cake is pretty straightforward – just make sure you do it on the plate you want to serve it on! There is no way you want to try to move this cake once done.
Between each layer spread a thin layer of frosting. As there are a lot of layers and then icing around the outside as well, you can get away with this being quite thin.
Once the layers are done, spread a thin layer of frosting around the outside and on the top of the cake. This layer is called the crumb layer, as it will pick up crumbs off the side of the cake and may be a bit messy. Make sure to not use all the frosting, you want to chill the cake after this layer and then do another layer over the top to finish it off. Then decorate, stand back and enjoy a wine (you have earned it!).
I made this cake the day before the party and kept it in the fridge overnight – you will have enough to do before the party to worry about the cake!