I would not have attempted these if I was not approached by Fairy Floss Official to make the cakes.
The cakes are alternating layers of vanilla chiffon sponge with a hint of lemon and whipped vanilla lemon white chocolate ganache, topped with marshmellows and rainbow sprinkles. It took me longer than expected for this batch of 20 cake in jars and 10 push pops as it's my first attempt.
I used a reduced egg yolk recipe so that the pink, blue and purple colours can appear pastel and sweet without adding too much colouring. Some butter is used in replacement of canola (or any vegetable) oil to add some richness to the cake while retaining the lightness. Although vanilla flavour was requested, I decided to add a tinge of lemon flavour to give the cake a more refreshing touch. I used Taylor & College's natural lemon extract paste.
Recipe below is for 20 8x12 cm jars and 10 2.5x7cm push pops.
Recipe for reduced yolk vanilla chiffon sponge with a tinge of lemon
Ingredients (makes six 25x30cm and six 15x15cm thick layer cakes, one for each colour of the rainbow):
Egg yolk batter
12 egg yolks
90g caster sugar
270g canola/vegetable oil
90g unsalted butter
420g full cream milk
2 tbs vanilla extract
1 tbs lemon paste (I used one from natural sources which has no colouring added. You may use other brands of essences/extracts or add some lemon zest although zest will affect the rainbow colours a little)
480g cake flour
3/4 tsp fine sea salt
Gel food colouring
(Divide into six equal portions to bake each colour separately. Quantities in brackets are for each round of baking)
36 egg whites (6 egg whites)
2 tsp cream of tartar (1/3 tsp)
480g caster sugar (80g)
1. Prepare a tray of water as base of oven (optional but it's to provide steam while baking). Preheat oven to 150°C. Set oven rack to second lowest position. Line a 25x30cm tray and a 15x15cm tray with baking paper. Combine melted butter and vegetable oil in a bowl. Combine milk, vanilla extract and lemon paste in another bowl.
2. Prepare egg yolk batter. Use a hand whisk or hand held electric mixer to beat egg yolks and sugar until pale and thick. Add oil and melted butter and beat until well combined.
3. Add a third of milk and whisk well. Add a third of sifted flour and salt and whisk until no trace of flour is seen. Repeat until all milk and flour are added.
4. Divide egg yolk batter into six portions. Colour each portion with a chopstick dip of gel food colouring.
5. Prepare the meringue. Do this one at a time for all six colours, unless you have many ovens and are able to bake more colours for each round of baking. In a clean metal bowl, beat egg whites with cream of tartar with an electric mixer, gradually adding sugar, until firm peaks form.
6. Quickly but gently fold the meringue into egg yolk batter in three additions with a spatula. You may want to pour the egg yolk batter into the meringue for the remaining last one-third to minimize the number of times you need to fold. Pour the batter into the prepared baking trays. Tap the trays to release air bubbles.
7. Bake for 15-17 minutes or until skewer comes out clean. Immediately remove from tray and cool with another baking sheet over.
8. Use round cookie cutters to cut out cakes from the various colours. Choose the size that is suitable. For my case it's 2.5cm and 8cm diameter round cutters. Use a serrated knife to halve each circle cut-out as the layer cake is quite thick.
The cakes needed to be on display for the whole day outdoors in warm Singapore so the frosting has to be able to withstand this kind of weather. My first choice would have been dairy cream, followed by swiss meringue buttercream in terms of taste but both are not suitable in Singapore's weather. I opted for whipped white chocolate ganache as the frosting base instead but included butter and shortening to reduce the amount of white chocolate used to reduce the overall sweetness while giving the frosting the stability needed in this weather.
Whipped vanilla lemon white chocolate ganache
515g heavy cream
900g white chocolate, chopped
105g unsalted butter, cut into small pieces
105g vegetable shortening, cut into small pieces
1/4tsp fine sea salt
1 tbs vanilla extract
1 tsp lemon extract paste
1. In a large microwave-safe bowl, place white chocolate, unsalted butter and shortening. Heat at medium power for 20 seconds and stir well. Repeat until everything is smooth and melted.
2. In a saucepan, heat heavy cream until it starts to bubble. Remove from heat and pour over melted chocolate.
3. Stir with a spatula in one direction until smooth and well combined.
4. Add vanilla, lemon extract and salt. Stir until well combined. Chill in the fridge for 10-12 minutes.
5. Use an electric mixer to whip the white chocolate ganache at low speed for a minute. Return the mixture into the fridge for a few minutes and whip with electric mixer until pale, light and fluffy.
Whipped vanilla lemon white chocolate ganache!
To assemble, place alternating layers of cake and pipe whipped ganache. Top it off with a bit of ganache, marshmellows and rainbow sprinkles.
Refrigerate until ready to display. The push pop containers are not airtight so I kept the whole lot in a sealed plastic bag. Here's a peek at my fridge!