Unassuming and simple from the outside, but when it’s cut into it has the most amazing layers of colour. This cake really does have the wow factor!
I’d been wanting to make this cake for a long time but hadn’t found an reason good enough to actually make it. I waited long enough and the perfect occasion came around – Rien’s brother, Daarek’s birthday. I knew this would be the perfect cake for him and I wasn’t wrong! He is always so complimentary with my cakes so I wanted to step it up for him and make him a birthday cake that was a bit special.
The inspiration for this recipe came from a lovely blog, Kerry Cooks. Her blog was the first place I remember seeing a rainbow layer cake that actually gave you a recipe to make the cake yourself. A lot of the American recipes use a boxed cake mix. Her blog has some fantastic tips which I was able to use and adapt slightly to create my Rainbow Layer Cake.
You may look at this cake and feel slightly scared, but there is really no need to be! You need to make sure you have the right equipment and then you’ll be fine. To make this cake as easy as possible, I bought the Easy Cake Layer Pan Set by Wilton from Lakeland. I’m sure there are plenty of places you can buy them online. One tip if you do buy these cake pans; do not believe them when they say they are non stick! I stupidly believed that they were the first time I used them to make an ombre cake and ended up with some cake getting stuck to the pans. I recommend lining the tins with baking paper to prevent this from happening. On her blog, Kerry used disposable pans which you can find in lots of supermarkets and pound shops which is a great tip if you don’t want to buy any new equipment.
The cake pan set is for 5 layers, so the recipe below will make you a 5 layered rainbow cake. Each pan is 6 inches which I think is the perfect size for this cake seeing as you are stacking 5 layers of cake with lots of buttercream. It also means each layer isn’t too thick. If I were to make this cake for myself, I would use cream cheese frosting like Kerry did. However most people, including Daarek, prefer buttercream so that is what I used.
You also need really good gel colouring to get the fantastic vibrant colours. The liquid food colourings you can buy in supermarkets just aren’t good enough. You need concentrated gel colouring which you can buy online or in shops like Lakeland and Hobby Craft. My favourite brand to use is Wilton because they have a great range of colours an can give you really bright colours without having to use loads of it.
When it comes to icing cakes I think it is definitely worth investing in a cake turntable. This allows you to smoothly turn the cake backwards and forwards when you’re decorating it which is a huge help! I also use a large off-set spatula to apply the buttercream to the cake holding it at a 90° angle. A spatula dipped in hot water and then dried is a great way of getting a smooth finish on your cake. There are lots of different techniques and ways people find help them, but this is what works for me.
What I like most about this recipe is this one cake mix will make enough for all 5 layers so you don’t have to faff around making different mixes. An obviously that it looks pretty amazing!
For the cake
225g butter or margarine
225g caster sugar
4 large eggs
1 tsp vanilla extract or vanilla bean paste
225g self-raising flour
2 tsp baking powder
- Preheat the oven to 180°C/160°C fan. Line you cake pans
- Add the butter and sugar to your bowl and cream until light and fluffy. Add the eggs one at a time starting on a low speed and increasing it after each egg has been added. I find this helps incorporate the eggs better. Add the vanilla and mix again before finally adding the flour and baking powder
- Split the cake mix equally into 5 different bowls. I do this by weighing my mixer bowl when its empty and then taking this away from the weight when it has the finished cake mix in. I then divide this by 5. You can do it by eye but I prefer to be exact as this will help make even layers
- Colour each bowl of cake mix a different colour – I coloured mine red, orange, yellow, green and blue but feel free to use whatever colours you like. Start with a small amount of colouring as a little bit goes a long way. You an always add more and make it brighter but you can’t make it lighter again!
- Pour each bowl of coloured cake mix into your prepared tins and bake in the oven for 10-15 minutes. They’re done when a cocktail stick comes out clean
- Allow the cakes to cool slightly in the pans before turning out onto a wire rack and let them cool completely
- Once completely cooled, level the cakes so that they stack more evenly. I do this with a cake wire which allows you to cut a clean level line using a serrated wire. You can use a knife but I find this works better and reduces the risk of making a mistake! I set the cake wire to the height of the cake that needs the most cut off it to make it level. You’re looking to take the smallest amount of cake off to make the cake flat
- Once the cakes are leveled, you’re ready for the buttercream!
For the buttercream
420g unsalted butter
840g icing sugar
4 – 6 tbsp milk
- Mix the butter and icing sugar together until pale and smooth. Add enough milk until it is a smooth spreadable consistency
- Starting with the blue layer, place one layer onto your cake board and then add a generous layer of buttercream. Repeat with all 5 layers
- Once all of the layers are stacked, it is time to apply the crumb coat. This locks all of the crumbs in place so that the final layer of buttercream is smooth and crumb-free. Do this by applying a thin layer of buttercream to cover the whole cake. At this stage it doesn’t have to look pretty. After you’ve applied your crumb coat, but in the fridge for at least 30 minutes for it to set slightly
- Once the crumb coat has become firm to the touch, you can now apply the final layer of buttercream. Make sure you use quite a generous amount of buttercream and take your time!
- You can decorate the cake however you would like. I chose to keep it completely plain on the outside and made some bunting to stick in the top
Make sure you check out Kerry’s blog http://kerrycooks.com/easy-6-layer-rainbow-cake-step-by-step/
Apologies for the photos not being the best, I always find it hard to take photos of cakes I have made for people. And I can’t take my usual kit with me!