If you’ve been anywhere near Pinterest or Instagram lately, you will have no doubt noticed the trend for unicorn cakes. And whilst I often like to avoid making anything ‘trendy’, because I’m just too cool for school, I knew that my daughter would absolutely love one for her upcoming 5th birthday. So after a good hour of scouring the internet for inspiration, I decided to make my own version.
- 315 g plain flour
- 1/2 tsp baking powder
- 1/2 ts baking soda
- 1/2 tsp salt
- 225 g unsalted butter (softened)
- 450 g sugar (caster/super fine)
- 3 large eggs
- 1 tsp vanilla extract
- 1 cup sour cream (235ml)
White Chocolate Buttercream
- 100 g white chocolate
- 200 g sugar (caster/super fine)
- 1/4 cup water
- 5 egg whites
- 1/4 cup 50g caster sugar
- 450 g unsalted butter (room temperature)
- Preheat oven to 180°C/350°F.
- Grease and line two 8-inch cake tins, which are at least 2 inches high.
- Sift together the flour, baking powder, baking soda and salt.
- In a mixer cream the butter and sugar until fluffy.
- Add the eggs, one at a time, beating well after each addition.
- Stir in the vanilla.
- Add half the dry ingredients, and stir until combined. Then add the sour cream and stir until fully incorporated. Lastly, add the remaining dry ingredients, and stop stirring as soon as they are incorporated.
- Scrape batter evenly into the prepared cake pans, and level the surface.
- Bake until the centre springs back lightly when pressed, about 40 minutes.
- Let the cakes cool in the pan, then invert onto a rack.
- N.B. You will need 2 or 3 batches of this recipe for a large celebration cake.
White Chocolate Buttercream
- Melt the white chocolate, either in the microwave or over a bain-marie. Boil 200g of sugar and ¼ cup water over medium-high heat, without stirring, bruising down the sides of the pan occasionally, until it reaches 118°C/244°F.
- As it cooks begin meringue so it's ready when syrup is done. Whisk the egg whites in a mixer until they become foamy, then add the ¼ cup of sugar, gradually.
- Carefully pour the hot syrup into the meringue in a steady stream with the mixer still on high speed. Beat the meringue for 10 minutes until the outside of the bowl is room temperature.
- Gradually add the butter in small pieces, and continue to beat until the buttercream is smooth. Add the cooled melted chocolate, and beat again to incorporate.
Having prepared my modelling chocolate the previous day, it was time to start experimenting with making the horn and ears.
For the horn, I rolled a piece of modelling chocolate into a long cone shape, using a fondant smoother to keep it free from fingerprints and as smooth as possible. Then I simply coiled it around a wooden skewer that I had propped up in a narrow vase. A bit of spray colouring was all that was needed to turn it into a magical unicorn horn!
The ears were a little trickier to fashion, but after a couple of somewhat failed attempts I discovered that it’s best to start by rolling a ball. If you then start to roll it into a sausage shape, you can start to softly point the ends. Then I simply cut my sausage ball into two pieces, and flattened them carefully to coax out the shape of the long triangular ears.
To create the inner ear area, you could cut out a coloured piece of modelling chocolate, but I thought it would be much quicker, easier, and more effective to simply make some recesses and brush them with a pink lustre dust. And I’m loving how these turned out! The addition of a couple of cocktail sticks is all that’s needed, and then they can be left to harden a little before they are attached to the cake.
I trimmed the tops and bottoms off my cakes, and stacked them using some of my own strawberry jam, then carved the top edge to make it more rounded and slightly more ‘head-shaped’.
To match the flavour of my modelling chocolate, I decided to make a white chocolate buttercream. This is made exactly the same way as a regular buttercream, but just with some cooled melted white chocolate added at the end – easy peasy!
Perhaps unsurprisingly, it’s a lot harder to get a smooth finish on a curved surface than a flat one, and I haven’t yet figured out a really good method. I have seen videos where people use a bent piece of plastic to create a consistent curve, so I tried giving that a go, although I was less than thrilled with the result!
Luckily, this wasn’t going to be too much of a problem, as I had decided to cover my cake with modelling chocolate instead of just buttercream. I made this decision for a couple of reasons: firstly, so that I can easily attach the eyes and flowers without risking upsetting the surface, and also because it’s super delicious. It’s a double win!
As I noted during my previous experiments with modelling chocolate, it’s not very malleable though. Smoothing it over the cake in one sheet is really difficult and ultimately doesn’t seem to be a viable option, especially on a cake of this size. Instead, I decided to wrap a long sheet around the cake, and suffer the seam at the back. And I could easily hide the join with buttercream flowers afterwards, as well as on the top of the cake, so it didn’t present any problems for this design.
I actually decided to patch up the top of the cake with a small sheet of modelling chocolate, and through a combination of squashing and carving, was able to get a pretty regular finish all over the cake, with a nice neat surface everywhere that counted!
I also decided to do the eyes in a lot more detail, and traced a pair of eyes from a My Little Pony character to create templates. Resolute in my decision not to use fondant, I made some ‘modelling chocolate’ using candy buttons, sometimes known as candy melts, or compound chocolate. That way you can get a completely white colour that is suitable for the whites of the eyes, and also super easy to dye to other colours. I also made another batch with some black candy buttons, as it’s very hard to achieve the colour yourself, and much easier to start off with something that is already dyed black. I rolled some thin strips of black modelling chocolate to define the eyes and add some lashes.
Overall I was delighted with how it turned out, and I reckon my next one will be even better!