This isn’t just a delicious recipe for a vanilla buttercream cake, I’m going to breakdown how to create the unicorn cake that’s been flooding our social media feeds for months. Even if you’re not going to be making a unicorn cake anytime soon, below is a detailed recipe on how to bake, prep and frost a basic 6-layer vanilla cake – which, if you’ve ever been asked to make a birthday cake, should come in handy, no matter how you decide to decorate it!
First up, I just want to say that I am absolutely aware that the unicorn cake trend is basically almost over. Well, if you’re a serious baker, instagrammer or following ‘baking trends‘ that is. But if you’re a 3 year old, then a unicorn cake is still VERY much a big deal! So when I got THREE requests in one week from various family members to make a Unicorn Cake, that’s clearly the universe telling me to post it. If I’m being asked for unicorn cakes from nieces, cousins and step-daughters then obviously you are all too! So, hopefully this post will encourage you to bake any little girl (or boy!)’s dream come true…
Tip #1: Never frost and decorate a cake on the day you baked it. In other words, always prep the sponge and frosting the day or night before. Freshly baked sponges are a wonky/collapsed cake waiting to happen – especially if you’re layering them 6-sponges high!
Tip #2: Freeze (or at least refrigerate) your cake layers. Frozen cake layers are rigid and cold which makes it easier to build a straight cake and also immediately sets the frosting so it’s sturdier. Since I learnt this trick it’s changed my life!
Tip #3: Make all the fussy decorations (like the unicorn cake ears/unicorn horn) a few days before so you’ve got less to worry about.
Tip #4: Get a cake turntable. It will make your life so much easier!
Getting the look of the main on the unicorn cake usually requires a lot of different piping nozzles, but if you’re not a good piper you can buy some of these mini meringues from any supermarket and use those – I popped them on my cake in between the buttercream because I love the crunch they add! Do you regularly bake birthday cakes? I would love to hear some of your tips and what creations you’ve made – post them in the comments below!
VANILLA BUTTERCREAM UNICORN CAKE
Makes 1 large 6-layer cake (20cm wide x 20cm high) or 35-40 cupcakes
Timeline: 2 hours for baking the sponges and prepping the frosting, 3 hours for assembling and decorating
Recipe adapted from the Hummingbird Bakery Cookbook
VANILLA SPONGE
160g salted butter, softened
560g caster sugar
480g cake flour
30ml (2 tbsp) baking powder
1/2 tsp fine salt
480ml full cream milk, at room temperature
1 tsp vanilla extract
4 large eggs, at room temperature
VANILLA BUTTERCREAM
1kg icing sugar
320g salted butter, softened
100ml full cream milk, at room temperature
1 tsp vanilla extract
Pink, turquoise and purple gel food colouring
TO DECORATE
Edible glitter and gold dust
200g White Fondant
3 large wooden skewers
Quick Dry (or you can use a little vodka)
To make the sponge, preheat the oven to 190 degrees celsius (170 if you’re using a fan-forced oven). Grease and line 6 x 20cm cake tins with baking paper. If like me, you don’t have 6 (who does), you’ll have to reline and bake the cakes in batches (which is perfectly okay).
Using an electric handheld or stand mixer (with the paddle attachment), place the butter, sugar, flour and baking powder in the bowl and mix on low speed until it resembles a sandy breadcrumb texture. Whisk together the milk, vanilla and eggs then, with the speed still on low, gradually pour the liquid into the dry ingredients. Beat the batter until smooth and light – about 2 minutes. Divide the cake batter in between your lined tins (if you’re OCD like me you can weight it so they’re all even – I used about 320g in each of my tins). Bake in the preheated oven for 20-25 minutes or until golden, springy to the touch and a skewer comes out clean. Allow the layers to cool completely before levelling them off by cutting off the tops with a bread knife. At this point I wrap the layers (usually with the base of the cake tin underneath to keep them steady) and freeze (or refrigerate) them overnight. Mix quickdry with edible gold lustre dust to form a thick paste and use a paintbrush to paint the unicorn horn, ears and eyes gold. Allow to dry.
To make the unicorn horn, ears and eyes; roll an egg-sized piece of fondant into a long sausages which tapers off at both ends (so both ends are thinner than the middle). Bring the two ends together to form a loop then twist the loop to form a unicorn horn! Insert a wooden skewer down the centre of the horn and allow to dry overnight. For the ears, form two large triangles then round the edges off. Place the triangle in the palm of your hand to give it a curved shape and allow to dry. Pinch off two small pieces of fondant for the eyes, roll into sausages, flatten slightly and form into curves.
To make the buttercream, place the icing sugar and butter in the bowl of a stand mixer with the paddle attachment and mix until it forms a thick sandy paste. Gradually add the milk and vanilla on low speed until combined then increase to high and whip until very white and fluffy – about 5 minutes.
To assemble the unicorn cake, identify your two most perfect, level sponges – they will be your top and bottom. Place one of them on a cake board. If you’re using a cake turntable, tape the cake board to the turntable so it doesn’t move around – I use masking tape. Top the first sponge layer with a big dollop of buttercream and use a palette knife to spread it out roughly. Top with the second sponge and press it down firmly so the buttercream underneath squishes out the sides (if you’re OCD like me, you can use a spirit level to make sure each level is straight). This is also where the cold sponges help as they’re rigid and set the buttercream almost immediately – so no wonky cakes! Continue layering sponge and buttercream, ending off with perfect sponge you reserved earlier. Using a palette knife scrape the frosting that squished out from the sides and spread that thinly all over the cake – this is called a crumb coat. Refrigerate until firm. Now cover the entire cake in a thick layer of frosting. Using a palette knife perpendicular to the turn table, scrape off an even layer of frosting to give you a smooth edge. Refrigerate again until firm.
To decorate the unicorn cake, divide the remaining buttercream into 3 bowls and tint each pink, purple and turquoise. Prepare 3 disposable piping bags with different nozzles – I used this one, this one and this one. The idea is to have large, medium and small nozzles to give varying textures. Place a different colour frosting in each. Insert the unicorn horn and ears into the top of the cake then stick the eyes on the front using buttercream. Now start piping varying sizes of swirls as the main starting at the top of the cake and working your way down the side. Sprinkle the main with edible glitter.
Good morning Kate. Thank you so much for your lovely recipes. I enjoy baking them SO much! I’m baking this for my daughter’s party. How do you manage to get your cakes completely level. When I attempt to level my cakes I always go skew. I specially bought a device to level the cakes at Value Baking Supplies, but it doesn’t work. ? How many servings will I get from the cake? I’m having 12 7-year old girls over.
Ps your cakes are so beautiful! I love making pretty, visually appealing cakes & your cakes are simply spectacular! ?
Hi Cornelia! Thank you so much for your kind words – I am thrilled that my recipes bring so much joy! Re level cakes, it takes practice – a really long bread knife works well and I do it by eye but you could also measure where you want to cut the cake, put toothpicks all along the side and use that as a guide. I’ve also literally just finished testing a way of baking cakes level for Food24 (so you don’t need to cut them afterwards). Wrap the baking tins in a wet towel! Here’s how to do it: Cut an old bath towel into strips that fit around your cake tin (make sure there are no threads hanging that could catch alight!) then submerge the towel in cold water for 5 minutes. Wrap the strip around the cake tin and secure it with safety pins. Pour in your cake batter and bake as normal .Re the servings, this cake will easily serve 12! Hope that helps – if you have any questions, DM me on Facebook or Instagram as I’ll be able to respond quicker there 🙂 Good luck and happy baking!
Thank you so much! I’m going to try out the technique you suggested with the towel! What a novel idea!
Thank you very much.
Btw, your brown butter cookies are one of my favourite cookie recipes ?
Ah that’s fabulous and so good to hear!
Hi Kate, would it be okay to ice and decorate the cake the day before? Or will the buttercream soften the fondant ears and eyes? Should I wait and add those on the day? thanks!
Hi Kate, loving the recipe but when I attempted it I weighed 400g for each cake tin and I only had enough for 4 tins? I can’t work out where I’ve gone wrong! X
Hi Gillian, you are absolutely right. My maths got the best of me there! The ingredients come to 1920g which if you divide by 6 gives you 320g. I’ve adjusted it now to be correct. Sorry for that! Hope it came out well in the end?
Ah mystery solved! I was doing a practise bake so was not the end of the world I was just stumped as to how I got it so wrong! X
Hello Kate
I just wanted to thank you for your recipe – I did a trial run ahead of my granddaughter’s birthday on 13 March. The sponge is moist and light.
Also thank you for the tips. I will only be doing 3 layers however.
You are so welcome! I’m glad you loved the recipe as much as I do! Hope everyone enjoyed the cake! x
It looks delicious. Thank you for sharing this recipe.