Never felt such a great sense of achievement from baking till I made this rainbow cake!

It’s essentially 7 layers of violet, indigo, blue, green, yellow, orange, red butter cake put together with in between layers of Italian buttercream. Each butter cake layer was a little more than a centimeter. While stacking the layers, before putting on the buttercream, coat a layer of sugar syrup on each cake.

Making the butter cake was relatively easy, decorating the cake required patience. It took about 4.5hrs making this cake.

I was too excited thus did not take a picture of all the 7 cakes after they were baked. Basically the batter was separated equally into 7 paper trays, added color, mixed well, spread evenly and baked for about 15min at 170°C.

butter cake
300g unsalted butter
275g sugar
6 eggs (60g each)
225g flour
5g baking powder
3g salt

1. Beat butter and sugar till light and fluffy
2. Sift all dry ingredients together
3. Add dry ingredients and lightly beaten egg alternately into mixture
4. Bake at 170°C for 15min or until skewer inserted in center comes out clean

Italian buttercream
200g caster sugar
60g water
4 egg whites (or 100g)
A pinch of cream of tartar
400g unsalted butter, cold and cubed
10g vanilla

1. Place water and sugar in a pot and boil to 120°C
2. While sugar heats, whisk egg whites and cream of tartar till soft peaks form
3. Pour hot sugar solution in a steady stream into whipped egg whites while whisking at medium speed. Once all sugar solution has been poured in, whisk at high speed till outside of mixer bowl feels slightly warm.
4. Turn mixer to medium, slowly add small pieces of chilled butter and add vanilla to taste