rainbow cake.

And so, I'm ending of 2012 with a big bang (cake) instead of a recipe round-up. I'm a terribly indecisive person and harsh critic. I'll pass on the headache, thanks. The rainbow cake has finally made its appearance on this blog! My cake mojo is definitely returning. I put it off for so long because of the number of layers I would have to bake. I had only two 5 inch cake pans at first- that would mean 3 rounds of baking and a hell lot more time. I had almost given up on the idea when I finally found another 5 inch cake pan, albeit a silicon one. These small sizes are really hard to come by, to me at least. Dang, I should have grabbed the 4 inch one too.

It turns out that the baking process didn't take too long at all. The layers were so thin that they needed only about 8 to 10 minutes. The slightly laborious part was the dividing of the batter into separate bowls to tint it with colouring. That's 5 bowls, 5 spoons for stirring and 5 smaller spoons to retrieve some dye out of their bottles. The last portion of batter stays in the mixer bowl. Oh and one more small spoon for the sixth dye.

I thought I put too much colouring in at first and the colours looked really intense but it all turned out well in the end. The only problematic one was the red. It turned out pink! The dye I used was Wilton's Christmas Red. I was deliberating whether to put in more dye- I wasn't sure if using more would result in a deeper pink or red. In the end, I let it go because I didn't feel like washing the spoon to scoop out more dye. (After I used a small spoon to scoop out the dye, I dunked it into the batter to get as much dye as I could off it before using a larger one to mix the batter.)

My cake layers were mostly flat but the slightest domes still made quite an impact on the overall levelness of the finished cake. One side of the cake is actually higher than the other, even though I tried to even it out as much as possible. I realized that the cakes baked in the silicon pan were completely and entirely flat. Can you guess which colours they are? I'll put the answer further down so that you won't accidentally spoil your fun!

It was definitely a wow moment when I sliced open the cake. Seeing the cake assembled and seeing the cake sliced open are a world apart. I was temporarily blinded for a moment. The colours are so lurid! At that point, all I was thinking of was that the effort was all worth it.

Maybe I should talk about the assembly of the cake. Because the rainbow cake is more about the idea of a colourful cake rather than the taste, it's a very flexible recipe. All you need is a white cake recipe, for easy tinting, and frosting of any kind. I've seen renditions using frosting to hold the layers together but I decided to use apricot jam instead. The purpose of the frosting between the layers in this cake is as what I've mentioned above just now, to serve as glue. You really want the frosting to be as minimal and discreet as possible to allow for a seamless rainbow appearance. I chose apricot jam because not only is it almost invisible as part of the cake, it also keeps the cake moister than frosting because of its higher water content. Plus, it's convenient too! Just melt down some jam and spread on cake. You'll be able to save on some butter (and calories) as well.

And now here's my answer to the question above: the orange and purple layers!

Here's to an exciting 2013!

Rainbow Cake
makes a 5 inch cake
adapted from America's Test Kitchen

Any white cake and frosting recipe goes here so if you have your favourites, please go ahead and use yours! I think a 5 inch cake is great because the amount of cake here is just right. Making larger cakes with minimal frosting in between will greatly skew the cake to frosting ratio to the undesirable end.

For the cake:
1 1/8 cups cake flour
1/2 cup whole milk
3 large egg whites
1 tsp almond extract
1/2 tsp vanilla extract
1 1/2 cups sugar
2 tsp baking powder
1/4 tsp salt
6 tbsp unsalted butter
food colouring- red, orange, yellow, green, blue and purple

Preheat oven to 350F. Prepare as many 5 inch cake pans you have.

Whisk the milk, egg whites and extracts together.

Mix the cake flour, sugar, baking powder and salt in the bowl of a mixer until homogenous. Add the butter and beat at slow speed until the mixture resembles moist crumbs.

Add all but 1/4 cup of the milk mixture to the butter mixture and beat at medium speed until the batter is smooth. Add the remaining milk mixture and beat until combined.

Divide the batter into 6 portions and tint each portion with a different colour. Pour each colour into a separate cake pan and bake for 8 to 10 minutes. If you have to reuse your pans, allow the cake to cool for 5 minutes in the pan before turning out onto a rack. Give the pan a quick rinse with water, dry it and then use again. It doesn't matter if the pan is still greasy.

Make sure all cakes are cooled before frosting. If you can, refrigerate them overnight so that they are cold and less delicate.

For the frosting:
1/3 cup sugar
2 tbsp flour
1/2 cup whole milk
2 tbsp heavy cream
1/2 tsp vanilla extract
1 stick butter, cubed and slightly cold

Whisk the sugar, flour, milk and heavy cream together in a medium saucepan. Bring to a boil, whisking constantly, until the mixture has thickened. Scrape into the bowl of a mixer, add the vanilla extract and whisk on medium-high speed until it has cooled completely. Add the cubes of butter, a few at a time, until all has been incorporated. Whisk for a while more until the frosting is fluffy and has turned paler. If it gets too soft, place the bowl in the freezer for 10 to 15 minutes and then whisk again.

For assembly:
1/4 to 1/3 cup apricot jam, melted

Start with the purple layer of cake at the bottom and spread a layer of jam on top. Place the blue cake layer and repeat until all the layers have been stacked. Also spread a thin layer of jam on top of the top layer to prevent cake crumbs from mingling with the frosting. Chill the cake until the jam has set, 10 to 15 minutes. Crumb coat the cake with frosting and chill until that layer of frosting has set, 10 to 15 minutes in the freezer. Frost with the remaining frosting and chill the cake until the frosting has hardened, about 4 hours.