Holly’s rainbowtastic cake by Juliet Sear
To recreate Holly's amazing rainbowtastic birthday cake, Juliet Sear used five layers of marble rainbow sponge filled with rainbow cookies and sweets and finished with rainbow buttercream - recipe below!
For the rainbow cookies
200 g (7 oz/1 ¾ sticks) soft salted butter, at room temperature200 g (7 oz/1 cup) golden caster sugar2 teaspoons vanilla bean1 large free-range egg, lightly beaten400 g (14 oz/3 1/5 cups) plain (all-purpose) flour, sifted, plus extra for dustingPreheat the oven to 180°C (350°F/Gas 4).
Pop your butter and sugar into a mixing bowl. Add the vanilla paste, or scrape out the seeds from the vanilla pod and add these. Mix on slow or beat by hand until just combined.
Add the egg and mix, still on a slow speed, or use a wooden spoon, until fully incorporated
Tip in all the sieved flour and continue to mix until a dough is formed. If the mixture is a little sticky, add a little more flour. If it’s a bit dry, add a few drops of water. You’ll know it’s the right consistency when the dough comes together without leaving sticky traces on the bowl and forms a nice, shiny, pliable ball.
Roll the dough out on a clean, floured surface – use plenty of flour to prevent sticking. Roll to a thickness of about 4/5 mm.
Once your dough is rolled out, cut your shapes out with cookie cutters or chosen card template
Use a palette knife or a thin cake slice to pick up your cookies and transfer to a baking sheet lined with baking parchment. Leave a gap of about 2 cm (1 in) between each one.
Place in the oven and bake for around 10–12 minutes (for small- to medium-sized cookies. Check after 10 minutes, as all ovens vary. The cookies should be golden brown, firm and springy to touch.
Cool on a wire rack and decorate as required
For the rainbow-marbled sponges
Juliet used a basic vanilla cake and dyed the cake batter with strong food colouring. Holly’s birthday cake used 5 x 10” round cakes which equates to 5.5 kilos in total of cake batter mix. This was split into 6 colours and divided between the tins.
The below recipe can be multiplied as necessary.
300 g (10 ½ oz/2 ½ sticks) soft salted butter, at room temperature, plus extra for greasing300 g (10 ½ oz/1 ½ cups) golden caster sugar2 teaspoons vanilla bean paste6 medium free-range eggs, lightly beaten300 g (10 ½ oz/2 1/2 cups) self-raising flour1 teaspoon baking powder
Preheat the oven to 180°C (350 °F/Gas 4)
Place the butter, sugar and vanilla or other flavourings into your mixing bowl and combine. Turn the speed to high (or if you’re using a wooden spoon, use plenty of elbow grease!) and beat until the mixture is very pale, soft and fluffy and the granules of sugar have disappeared.
Add the beaten egg, about one-quarter at a time, beating it in slowly each time
Add the flour gradually, one-quarter at a time, mixing gently on a slow speed, until it has mostly been incorporated. Fold with a metal spoon if doing this by hand. Take care not to mix or beat vigorously or your sponge can turn out a bit tough.
If you are dying the cake do this at the end with strong food colouring
For a larger cake, begin checking if it’s cooked after 25/30 minutes. The 10” round take approx. 45-50 mins with 1.1kg of batter in each tin.
Remember all ovens vary so, if in doubt, use an oven thermometer. The cakes should be a light golden brown, springy to the touch. A sharp knife or metal skewer should come out clean and free of mixture.
Leave to cool for a couple of minutes in the tins then turn out onto a cooling rack
For the buttercream
(Holly’s cake used 5kg of buttercream - this recipe makes around 750g, multiply as necessary)
1 vanilla pod (seeds scraped out), or 2 teaspoons vanilla bean paste250 g (9 oz/2 ¼ sticks) soft unsalted butter2 teaspoons vanilla extract500 g (1lb 2 oz/icing (confectioner’s) sugar, sieved
If you do have an electric stand mixer then use this with the beater or paddle attachment. Otherwise, use handheld beaters or a wooden spoon. Scrape the seeds from the vanilla pod and cream the butter with the vanilla seeds and extract until very pale, creamy and smooth.
Add about one-quarter of the icing sugar. To make sure the sugar doesn’t puff out in clouds and cover your kitchen, mix slowly at first. You can also place a damp tea towel over the bowl. Once the icing sugar is all mixed in, beat at a high speed for about 1 minute until the mix is really creamy and pale. It will take you a few more minutes by hand.
Continue adding the sugar in one-quarter increments, taking care to beat it in well after each addition
Beat the buttercream at high speed for 1–2 minutes until it’s lovely and fluffy and pale. Use strong food colourings to dye if required.
For the rainbow meringue
75 g (2 ½ oz/2/3 cups) icing (confectioner’s) sugar75 g (2 ½ oz/1/3 cup) white caster sugar3 medium free-range egg whites (at room temperature)Pinch of salt
Large plastic piping bagLarge round nozzle with a 1cm approx opening for piping the clouds, or you can just snip a larger hole in a bag
Preheat the oven to 120 °C (225 °F/Gas 1/2) and line your baking tray with parchment paper. If you’re using a template, trace any shapes onto the paper first and turn it over.
Place the sugars in a bowl and stir with a spoon or whisk to combine
Whisk the egg whites and salt in a completely clean and grease-free bowl until you reach stiff-peak consistency
Add one-third of the sugar and whisk thoroughly on a fast speed for about 30 seconds. Repeat with two further additions of the sugar until you have a stiff and glossy mixture. Colour some of the meringue in rainbow shades for the stripes, but save enough white for the clouds.
Place in a piping bag and use as required. Bake them for about 20 mins then turn the heat down to 100 degrees and bake for a further 50 mins, checking they do not colour on the clouds, if need be a longer bake at 90 degrees will keep your clouds white. Leave them in the oven with the door closed until completely cool and dried out.
To sandwich together use a little white royal icing or buttercream