Purple Ombre Sprinkles Cake

Tomorrow is my birthday, and though I've reached the stage where birthdays don't excite me anymore I thought I would do a fun cake for this week since I didn't have anything else planned. I wanted to do a crazy cake that was 100% just for me, just all the things I loved and have wanted to put into a birthday cake. And that means sprinkles and lots and lots of purple. Enter Steph's crazy purple ombré sprinkles cake with salted buttercream. I've always been in complete awe of all the amazing colourful layered cakes I see on different blogs, especially the gorgeous ones that have the ombré effect. I never though I'd be able to pull off one, it seemed like something that required patience and to be neat and meticulous and I can't do any of that very well. But since this cake was entirely for me, the only person I would be disappointing is myself if I failed so I went for it.

I've had a really bad week. Really bad. At first the thought of baking while in the middle of this horrible week seemed like a terrible idea but then I remembered that baking is my happy place, my therapy. So I pottered around the kitchen and lost myself in this recipe and it really did make me feel better. I used the most reliable yellow cake recipe I knew of, from my Le Cordon Bleu cooking book. It's deliciously buttery, the batter is stable enough to deal with a lot of mixing and the texture and moisture of the cake works well for layered cakes. It's one of the first cakes I ever made while learning to bake. The original cake is for a 3 layered cake, but I split up the mixture into five layers so I could get a good range of purple shading. I only have one 20cm cake tin which meant I had to bake 5 cakes, one after the other, cleaning, regreasing and lining each tin in between. It took a while and took my mind off my crappy week. And it also reminded me once again that I need to buy more cake tins.

I used Wilton colouring gel and it worked absolute wonders. I usually find it's way too hard to to get the perfect shade of purple when using red and blue colouring so I saved myself the trouble and got some violet colouring. I am absolutely in love with the effect of the shading, and surprised that I managed to get the gradient of shading right. I did a little happy dance when I cut into the cake for the first time. And I also chortled smugly at the recent memory of someone who worked at a professional bakery telling me that to get this kind of shading between each layer would require someone to make 60 cake layers before they got it right. Haha whatevs.

I decided to use the leftover blackcurrant jam from my Ribena Cupcakes from last week. I love jam in cakes so much, it keeps them moist and gives it a nice burst of flavour. And it worked great since it was purple too. I used my favourite icing, the simple salted butter icing that I can't stop using recently. I originally was planning to do a crazy bright purple icing but decided to keep it simple and white, to give you the surprise of the bright colour when you cut into the cake. It works so well, as learnt from the epic Whisk Kid rainbow cake that is burned into my memory as the best cake ever. Originally I wanted to cover the entire cake in chocolate freckles because I recently rediscovered my love for them. But when I started to cover the cake in the freckles I realised the cake looked pretty damn ugly, like it was covered in festering warts. Lovely, I know. So I went into full panic mode and ripped off all the freckles and started slapping rainbow sprinkles all over the cake to cover up the mess I'd made. Sprinkles EVERYWHERE. I even found a sprinkle in my belly button when getting changed later. It was a mess, but my cake ended up looking like one giant freckle and that is kinda awesome. It reminded me of this amazing cake from Sprinkle Bakes. And check out the stunning Vanilla Malt Sprinkle Bark Cake Lisa made me! Sprinkles make everything better.

Purple Ombré Sprinkles Birthday Cake
(makes one round 18cm 5-layer cake, yellow cake recipe adapted from Le Cordon Bleu Complete Cooking Step-by-Step)
Note: Sorry US readers, I didn't have time to measure the ingredients in cups so I could convert the measurements for you, you'll have to convert it yourself or use some kitchen scales for this one! Thanks to Reanna for posting the US conversions for the recipe in the comments below, you can see them here.

For the cake:
355g plain flour
1 tbsp baking powder
1/2 tsp salt
225ml milk
2 tsp vanilla extract (I used 1 tsp extract and 1 tsp vanilla bean paste)
400g caster sugar
225g unsalted butter, softened
4 medium eggs
Purple food colour (I used Wilton violet gel colouring)
Jam to spread between layers, I used blackcurrant jam but you could use grape or strawberry, or double the amount of icing and use that

For the icing:
500g icing sugar sifted (easiest way to sift is by pulsing in a food processor)
275g salted butter (about 2.5 sticks)
Extra table salt to taste
Optional: sprinkles to decorate

Preheat oven to 180°C (350°F) and grease whatever 18cm round cake tins you have (I only had one so I had to bake each cake one after the other). If you only have 20cm cake tins I'd recommend splitting the batter into only 4 layers instead of 5. Line the base of tins with baking paper and grease paper and dust tins with flour. Combine flour, baking powder and salt in a medium bowl and set aside. Mix milk and vanilla together in a measuring jug.

Using an electric mixer on low speed, beat sugar and butter in a large bowl until blended. Increase speed to high and beat for 2 mins or until pale and creamy. Reduce speed to medium low, add eggs 1 at a time, beating well after each addition. Alternately add flour mix and milk mixture, beginning and ending with flour mixture (I did it by adding 1/4 of of the dry mixture followed by 1/3 of the wet mixture at a time). Beat until smooth, occasionaly scraping bowl with a spatula. Divide mixture evenly into 5 medium bowls (I did this by measure the batter, it ended up being about 300g per bowl for me). Leave one bowl of batter white, then very gradually add colouring to each bowl and gently fold it into the mixture, adding slightly more colouring as you do each bowl so that the 5 bowls give you a even gradient of colour.

Pour batter into prepared tins and bake each layer for about 15-20 minutes or until a skewer into the centre comes out clean and the outside is golden. Cool in tin for 5 mins and then turn out onto wire racks to cool completely. Prepare the icing; remove butter from fridge 30 mins before starting and chop into small cubes. In a large mixing bowl, beat butter on high with an electric mixer until smooth and fluffy. Reduce speed to medium-low and gradually add icing sugar until combined, then increase speed to high and beat until pale and fluffy. While still mixing, gradually add any extra table salt to taste if needed.

Prepare cake for icing, you may need to trim the tops a bit to make sure they are level. Layer cakes with jam (or more icing). Crumb coat the cake with some of the prepared icing and chill for 15 mins. Cover the cake with more icing, smoothing out with a spatula (I use an offset spatula that I keep clean and warm by running under hot water to get it smoother). If decorating with sprinkles, it can get pretty messy so place your cake in a large container that will catch any of the sprinkles that will run off the cake as you try to stick them on the sides of the cake. Serve cake at room temperature, store cake in the fridge in an airtight container.