Rainbow cake

Cuts into 18 slices Prep 2 hrs Cook 45 mins-1 hr 50p a slice 601 kcals, 29g fat, 18g sat. fat, 47g sugar un-iced sponges only

You will need 3 x these ingredients for six sponges (see below to make a seventh layer) 125g butter, softened, plus a little

extra for greasing 225g plain flour 150g golden caster sugar 3 medium eggs (very important to use the correct size) 3 tbsp buttermilk ½ tsp baking powder pinch of salt 1 tsp vanilla extract edible food colouring – red, orange, yellow, green, blue and purple, plus optional pink (see right)

FOR THE ICING 1 tsp vanilla extract 3 x 250g tubs light cream cheese

or mascarpone 350g icing sugar

Heat oven to 160C/140C fan/gas 3. Grease 2 x 20cm round sandwich tins and line the bases with baking parchment. Tip all the sponge ingredients, apart from the food colouring, into a mixing bowl, then beat with an electric whisk until smooth.

Working quickly, weigh the mixture into another bowl to work out the total weight, then weigh exactly half the mixture back into the mixing bowl. Pick 2 of your colours and stir a little into each mix. Keep going until you are happy with the colour – the colour of the batter now will be very similar to the finished cake, so be brave! Scrape the different batters into the tins, trying to spread and smooth as much as possible – but try not to waste a drop of the batter – a rubber spatula will help you. Bake on the same oven shelf for 15 mins until a skewer poked into the middle comes out clean.

Gently turn the cakes out onto a wire rack to cool. Wash the tins and bowls thoroughly, and start again from step 1 – this time using another 2 colours. Unless you’re making the optional pink layer, repeat one more time to get 6 sponges, all of different colours. Leave them all to cool.

To make the icing, very briefly beat the vanilla and cream cheese or mascarpone with an electric whisk until smooth. Sift in the icing sugar and gently fold in with a spatula. Be careful – the more you work it, the runnier it will get, increasing the chance of splitting.

Smear a little icing on your cake stand or plate – just a splodge to stick the first sponge. Start with the red, then spread with some icing right to the very edge. Repeat, sandwiching on top the orange, yellow, green, blue and finally purple sponges. Spread the remaining icing thickly all over the sides and top of the cake.

Make an extra layer

The recipe makes six sponge layers, but you can make one extra layer by halving the cake quantities and baking a single sponge dyed pink q ÕÃi Ì Ã >Ã Þ ÕÀ ÃiÛi Ì >ÞiÀ° it’s not strictly necessary, the cake will still look fabulous with six – but why not!

How to create perfect colours

To make sure you’ve got a good balance of colours, test your V ÕÀ }à > ÌÌ i Ü>ÌiÀ wÀÃÌ° We used The SK Professional Paste Food colour and Quality Food colour (QFc) paste ranges from Squires ( squires-shop.com ®° LÕÞ « Ìà Ài`] À> }i] ÃÕ y ÜiÀ] fern, hyacinth, purple and pink (if Þ Õ½Ài >`` } > ÃiÛi Ì >ÞiÀ®° In supermarkets, Dr Oetker has a range of gel food colours – look for the ÌÌ i ÌÕLiÃ Ì i L> } > à i° 9 Õ½ ii` bright red, neon orange, sunshine yellow, lime }Àii ] Ã Þ L Õi] Õ ÌÀ> Û iÌ > ` Ì « °

Top tips for a RTQHGUUKQPCN ƂPKUJ

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