If you’re looking for a recipe for Easy 6-Layer Rainbow Cake, you came to the right place! You’ll love it if you’re a big kid at heart! Lots of people have made my Rainbow Cake with success (see the comments!) and I’m sure you will too – it’s an easy recipe that’s even suitable for cake beginners!
Rainbow Cake is THE perfect cake for any celebration. Fun, pretty, delicious and AWESOME, Rainbow Cake never fails to make everyone smile!
There are not enough exclamation marks in the world to convey my excitement for rainbow cake. I first came across this awesome version over at sweetest blog ever Sweetapolita. I also came across this great version by Whisk Kid.
All the recipes I found used Swiss meringue frosting and often cake mixes, so I decided to make a UK version, using a simple victoria sponge recipe (with the quantities doubled) and cream cheese frosting. It worked a treat! And it tasted delicious too.
I’ll tell you a secret – I was actually really intimidated by the idea of making a rainbow cake.
A few things to note about making this cake:
- I baked my cakes in small, disposable tin foil ‘flan cases’ that I found in Wilkinson’s (I used these ones, which are 6 inches. Supermarkets also increasingly sell disposable cake cases, in loaf and other shapes. But don’t worry if you can’t find anything like this, you can just use regular cake tins – depending on how many you own, you’ll need to cook the cakes in stages (if you own three, two stages isn’t too much hassle, if you only own two cake tins I would consider buying/borrowing another one).
- My cake had very thick layers and ended up very tall, because I used 6 inch pans (they were the only disposable pans I could find at the time – they’re now widely available in 6,7, and 8 inch sizes – try Wilko’s, the pound shop and your local supermarket). If you’d prefer your rainbow cake to have thinner layers and be less skyscraper like, simply use 8 inch can tins rather than 6 inch as I did.
- You will need to purchase concentrated thick colouring for this recipe. These are called gel or paste colours and come in little pots, at about £2.50 – £3.00 each. The best places to get these from are online (eBay) or a cake decorating shop (if you live in/near a city, you’ll be fine – Nottingham has two large ones) – none of the ranges sold in supermarkets (Dr. Oetker gel colour tubes) are nearly as good – though you could go with it if you’re desperate, the colours won’t be as vivid and rainbow like. See the bottom of the post for links and details of what colour I used for each rainbow layer.
- I recommend making my cream cheese frosting, as the cake, a day or two ahead of when you plan to stack and decorate the cake. So the ideal rainbow cake timeline for optimal results (not saying you can’t do it in one day / one evening, but this will give an easier, less stressful decorating process) is to bake the cake layers and make the frosting on the Saturday, let the layers cool completely, wrap in clingfilm and pop into the fridge, then make the frosting on the Sunday morning, and add three / four thin layers of frosting to the outside of the cake over the course of the day to serve that night.
- 350g self raising flour
- 3tsp baking powder
- 350g soft soft butter
- 350g caster or light brown caster sugar
- 6 large free range eggs (I tend to go for happy eggs)
- 1 tablespoon vanilla extract
- up to 40ml semi-skimmed milk
- 100g butter, soft
- 250g cream cheese, at room temperature
- 600g icing sugar, sifted
- First, preheat your oven to gas mark 4/170 degrees/360 degrees Fahrenheit and mix up your cake batter in the usual way - cream your butter and sugar until combined, add eggs one at a time followed by a little of the flour and mix well before adding remaining flour, baking powder and vanilla extract. If your mix is a little thick as mine was, add up to 40ml of semi-skimmed milk - adding a tablespoon at a time and stopping when you get to a consistency that you're happy with.
- Next, divide your mix into 6 bowls (including your original bowl) to do your colours. I divided my mix by eye, not bothering to weigh my mixture and divide it exactly equally.
- Drizzle on some of your red gel colour and mix in. Keep adding and mixing a little until you have the vibrant shade you want. Its actually very hard to go overboard with gel colours, but don't add too much at once (not more than a quarter of a teaspoon). Ten minutes and an aching arm later, you'll have a beautiful rainbow of cake batters!
- Pop them into the oven and keep a close eye on them - you don't want them to get overly browned. I rotated my cakes on the oven shelves throughout the cooking time (mine took around 20 minutes total), taking them out as soon as a skewer to the centre came out clean.
- When your cakes are cool, preferably wrap them in clingfilm and pop them into the fridge for a day. This will really make the cake much easier to decorate.
- Melt the butter in a heat proof bowl in the microwave for 20-30 seconds, until on its way to being completely melted. Thoroughly whisk the butter until no lumps remain. Whisk in your cream cheese, again until no lumps remain.
- Prepare your icing sugar, and then sieve it in to the cream cheese mixture 150g at a time, stirring gently with a wooden spoon between each addition. Add approx 1 tbsp freshly squeezed lemon juice (if you have it) - it won't make the frosting taste lemony, but it will just cut through the overwhelming sweetness.
- When all the icing sugar is incorporated, pop the frosting into the fridge to chill. As with the cakes, ideally, do this the day before you want to decorate the cakes.
- Put a little of the cream cheese frosting on the plate or cake stand you'll be using to adhere the first layer of cake. Pop it onto the centre of the plate, and then frost and put on the next layer. Careful not to use too much frosting, as the weight of the cake will push it out the sides of the cake- just a thinnish layer is best. After the first three layers, put the cake into the fridge for thirty minutes to chill.
- Continue stacking the cake, taking care to position the layers as evenly as possible, so that the sides of the cake are as straight as they can be.
- Apply a crumb coat of frosting to the cake, filling any gaps between layers. The colours of the cake will be very apparent, but don't worry. Chill for 1 hour.
- Apply a second coat of frosting. Chill for 1 hour.
- If necessary, apply a third coat.
– What colours will you need for your Rainbow Cake? –
Food colouring! But not just any food colouring. NOT the liquid ones of your childhood, although they do seem to be phasing those out now in favour of gel versions that you can get even in the supermarket. The ones I use are Sugarflair and Americolor and I get them from this little exclusive bakery supplies shop – you might have heard of it, its called eBay!
I love getting my gel colours from eBay because they’re cheap (cheaper or at least the same price as any baking supply shops I’ve visited) with free postage, plus its just easy and convenient. To make the cake, you’ll need these colours
Red – Christmas Red by Sugarflair
Orange -Melon + Christmas Red, both by Sugarflair
Yellow -Melon by Sugarflair
Green -Mint green by Sugarflair
Blue -Baby blue by Sugarflair
Purple – Electric purple by Americolour – I have tried and failed to get a bright purple colour using sugarflair (grape violet which is the only purple they do). If you want a bright purple, I recommend getting the americolor version.
The Americolour was from an American seller who combined postage, so they worked out to cost about £3 each whereas the Sugarflair colours cost about £2.50 each. If you haven’t used gel colours before, this might seem expensive but they go a looooong way – and last forever.
This cake would be super duper awesome for a kids birthday party…. especially if you kept the rainbow part a secret… can you imagine?
Rainbow cake makes me so happy. Oh and did I mention that rainbow cake is just the beginning? Check out these amazing ombre cakes which use exactly the same method.