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Richard’s Rainbow Cake. Request bake #1

July 7, 2011

One of the features of this blog is that if you see something you’d love to bake but don’t have the time or perhaps even the inclination, you can request that I bake and blog it. This is the first of the “request bakes” (though admittedly a verbal, not internet request)

So, without further ado I bring you Richard’s Rainbow Cake.

You can find the full recipe and instructions at the bottom of this post

I was idly looking at some blogs at work one evening and chatting to my colleague Richard about them. In particular he noticed the rainbow cake that I was looking at. I can’t remember how it happened or even which page I saw it on, as it seems that there has been a rainbow baking frenzy recently (see below), but the conversation ended up with me promising to make a rainbow cake for him. A few months of gentle pestering later and it just so happened that I woke on Tuesday morning in the mood to bake something colourful. You can find the full recipe and instructions at the bottom of this post.

This cake was a lot of fun to make, very rewarding in terms of the smiles it brings, and not nearly as time-consuming as might be expected. It took less time than the Sweet and Salty Cake. This is mainly due to the fact that each layer is very thin and therefore cooks very quickly.

However, if you don’t like washing up then this might not be the project for you. I had two loaf tins which I used on a rolling rotation. You also need separate bowls for each colour of cake batter and either a lot of spatulas (what is the collective term for spatulas? A scrape?) or one spatula which you wash and wash and wash again in between every colour. Contamination is bad for rainbow integrity!

My main concern when pondering this bake was that the batter should be pale enough for the colours to really shine through. After having a look at various generic sponge recipes I decided that it was safest to go with the tried and tested combined wisdom of Sweetapolita and Whisk Kid. Their “white cake” recipe doesn’t use any egg yolks which means that the batter is a completely blank canvas. I was also worried that this would be very much a case of style over substance and that the cake would taste a bit “meh” but it didn’t – Hurrah! It was a very moist vanilla sponge. Though as you will see below I opted for a lemon cream cheese icing rather than the sweeter (and more daunting) swiss meringue buttercream.
I used Sugar Flair paste food colouring. I think you’d struggle to get a bright enough colour from regular liquid colouring. I know they are expensive compared to the supermarket brands, but you use so much less and get much better results that I do think it’s worth it. I’m looking forward to seeing if Silver Spoon’s “Colour Creators” which BakingmadUK recently mentioned will hold up to the test when they launch in September. I think that a shaded Paul Klee-esque cake might be a good test for those. Watch this space and keep reminding me.
To my great surprise. my only real problem with this bake was that I ran out of frosting before I could get a really smooth finish on the first layer of icing (I now know that this is the “crumb coat” – I’m learning). Normally, you’d rough-ice the cake in buttercream, put it in the freezer for 10 mins to harden up, then take it out a do another super smooth top layer or cover in royal icing. This is particularly useful if you want a royal icing finish without having to use marzipan underneath. I had just enough cream chesse frosting to fill in the gaps but not to get a really nice finish. Also, I could have done with a bit more royal icing as I ended up with a bit of a patchwork around the ends of the cake (sneakily avoided in my photos – oh yes, the camera does lie)
Lots of people have “been there, baked that” before me and since tweeting about this I’ve discovered that not only does @Ms_McJones plan to bake a rainbow, but @kaycrayola and @LittleNeng have done so already. Below is a little selection of the ones that really made me want to give it a go.

The original: The Whisk Kid
The interactive: Sweetapolita
The British: Rhubarb & Rose
The sprinkled: Bourbonatrix
The coconut: Sunshine’s Baking (needs translating)
The epic: Darius, via twitter

And finally, the recipe:

Rainbow cake

(from Sweetapolita and The Wisk Kid)

226g butter, room temp
466 g sugar
5 egg whites, room temp – it’s easiest if you have these all in a jug or bowl in advance
2 teaspoons vanilla bean paste
3375g plain flour
4 tsp baking powder
½ tsp salt if your butter is not salted
355 g milk, warmed for 30 sec in microwave to bring to room temp
Red, orange, yellow, green, blue and purple gel / paste food coloring (or you can mix the colours you have like paints!)

+ 1 x cream cheese icing and 2 x royal icing packs

Preheat the oven to 350F / 180C . Grease and line as many cake tins as you have. I used loaf tins but the original recipe uses 9 inch rounds.

Sift together the flour, baking powder and salt.

Cream the sugar and butter, then add the egg whites and add them a little at a time. Add the vanilla and mix until fully incorporated. Then, alternating between wet and dry, add the milk and flour mixture in two parts.

Divide the batter between 7 bowls (or 6 if you’re not planning to differentiate between blue and indigo. I did though, so I shall frown on you if you don’t) To do this you need to find your inner science-chef and weigh the whole batter, divide by number of layers and weigh out accordingly. It’s important if you want it to look even.

Colour each bowlful of batter. I use cocktail sticks to dip into the colouring pots and then into the batter. You could use teaspoons but to be quite honest there’s enough washing up already. If you are in any doubt that the colour is not intense enough, make it brighter. Pour the batter into the baking tin and thwack it on the worktop to make sure it is flat. Bake for 10-15mins.

When you remove them from the oven, let them rest on the cooling rack, in the pan, for ten minutes. Then flip, cover, and stash them in the fridge or freezer to cool quickly.

Lemon Cream Cheese Icing

175g Cream cheese
450g Icing sugar, sifted
125g Unsalted butter, at room temperature
Zest of 1 lemon

Throw it all in a bowl and beat. A lot. Until fluffy and smooth

Decide on your order and stack them up, spreading a thin layer of cream cheese icing in between each one. spread more icing around the edges until roughly smoothed over the entire surface. This is the crumb layer. Put the whole lot in the freezer for 10 mins. Meanwhile, roll out the royal icing. When the time is up drape the royal icing over the top and smooth down. If you have one of those nifty icing-smoothing-paddles, even better. If you want to draw on it like Sweetapolita’s doodle-cake then you can get the icing pens online or at Jane Asher‘s shop

Finally, stand back and think…” oh, that’s it then”. Feel a little exhausted and underwhelmed. Now cut a slice…..WAHOOOO.. that looks brilliant!



3 Comments leave one →
  1. July 8, 2011 12:06 pm

    My sister (kaycrayola) is really chuffed you included the tweet with her rainbow cake!

    • July 8, 2011 2:49 pm

      Oooh! It’s your sister…even better! Thanks for commenting 🙂

  2. July 10, 2011 4:11 pm

    I had some, it was delicious and looked amazing!! Really loved the lemon, so fresh. Well done!

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