Rainbow cake

Who could resist a rainbow cake? I love colourful things, so I super adore my rainbow cake!! This is the first time I baked something so pretty looking, and I just cannot stop praising how beautiful it is. I really really love my rainbow cake! Totally didn't expect it to turn how so perfectly looking. However, of course the cake isn't totally perfect. This is the sweetest cake that I have ever baked. And if you noticed, I have low tolerance for sweetness. Thus, this cake is just not good for my taste buds.

Recipe adapted and modified from ladyironchef
Originated from whisk kid

Instead of using the Lemony Swiss Meringue Butter-cream from original recipe, I used vanilla buttercream recipe from mysweetandsaucy instead.

CAUTION:THIS CAKE IS VERY SWEET SO PLEASE REDUCE THE AMOUNT OF SUGAR IN BOTH CAKE & CREAM.

White Cake
226g unsalted butter, at room temperature
2 1/3cups (426g) granulated sugar
5 large egg whites, at room temperature
2 teaspoons vanilla extract
3 cups (426g) all purpose flour
4 teaspoons baking powder
1/2 teaspoon salt
1 1/2 cups milk at room temperature
Red, orange, yellow, green, blue and purple gel paste colouring

Vanilla Buttercream
340g unsalted butter
7.5 cups icing sugar
1.5 teaspoon salt
4 tablespoons whole milk
3 teaspoons pure vanilla extract
3 teaspoon fresh lemon juice

for cake:
1. Preheat oven at 175 deg cel. Butter and line as many 9" round pans as possible.
2. In a large bowl, sift flour, baking powder and sat. Set aside.
3. Cream butter and sugar on high speed using mixer until fluffy. Switch to medium-low speed and add in vanilla extract and egg whites slowly. Mix until fully incorporated. Change speed to low, using wet-dry ingredient method, add in 1/3 milk 1/3 flour. Keep alternating, ending with flour mixture. Mix well.
4. Divide the batter into 6 portions. (Can be divided equally by weighing) then add in gel colourings into each portion. Pour one portion into one pan and bake each for about 15min.

for buttercream:
1. Cream butter and salt for 30secs.
2. Add milk and half icing sugar and beat until combined.
3. Add rest of the icing sugar, vanilla extract and lemon juice and beat.
4. Beat on high speed for 5-6min or until fluffy.

tips/notes
As mentioned, this recipe yields a very sweet cake (See flour-sugar ratio-1vs1!!) Hence I would definitely suggest that you reduce sugar amount. For cake I reduced to about 320g of sugar while for buttercream I only used 3 cups of icing sugar and yet I still produced a super sweet cake. But again, it's according to your own liking and preference.If you have a sweet tooth, go ahead!

You would need to use GEL colourings instead of liquids ones to obtain a vibrant result. Liquid colourings would probably give your pastel coloured rainbow instead. Also, you may buy the primary colours only (red, yellow, blue) and mix them to get orange (red+yellow) and purple/violet (red+blue). I bought wilton's gel colouring that comes in a pack of 4 colours (red,orange,yellow,blue)and I had to mix the colours to get green and purple. It turned out quite well right?

This cake is actually quite plain in terms of taste (definitely not in terms of the look) hence I would suggest that you add in some decorating, like how I used biscuit crumbs for the coating. Definitely makes the cake more yummy!

I baked this cake for my friend's birthday. I love everyone's reaction when the cake was cut and the magic was revealed-RAINBOW! Everyone started to get really excited and many were busy snapping photos of this gorgeous cake.


I have awed all my friends, and now it's your turn to impress people with this magical rainbow cake!

Good luck! :D