Bake a rainbow! A showstopping celebration cake

Feeling creative? Why not make this delicious showstopper for a birthday or special anniversary?

RAINBOW CAKE

This colourful bake takes a little time, but it’s worth the effort.

CUTS INTO 30 SLICES

PREP 1½hr, plus cooling and chilling COOK about 1½hr

FOR THE CAKE

• Oil, to grease

• 200g raisins

• 550g unsalted butter, softened

• 750g light brown soft sugar

• 1tbsp vanilla extract

• 1tbsp mixed spice

• Finely grated zest 1 orange, plus 1tbsp juice

• Finely grated zest 1 lemon, plus 1tbsp juice

• 12 medium free-range eggs

• 850g plain flour, sifted

• 2tbsp baking powder

FOR THE BUTTERCREAM

• 825g unsalted butter, softened

• 1.5kg icing sugar, sifted, plus extra to dust

• 1tbsp almond extract

• 3-5tbsp milk

• Yellow, green, blue, purple and pink food colour paste/gels

• Mini chocolate eggs, optional

1 Preheat the oven to 180°C (160°C fan) mark 4. Lightly grease 2 x 20cm round, loose-bottom cake tins, each about 9cm deep. Line the bases and sides with baking parchment, making sure the parchment is 4cm taller than the sides of the tins. Wrap the outside of the tins with a strip of newspaper, seven layers thick, secure in place with string and trim to the same height as the parchment.

2 To make the cakes, in a small pan bring the raisins and 175ml water to the boil. Set aside. In a very large mixing bowl, using a handheld electric whisk, beat the butter, brown sugar, vanilla, mixed spice and citrus zests until light and fluffy, about 5min. Beat in the eggs 1 at a time. Beat in a little of the flour if the mixture begins to curdle.

3 Blitz the raisin mixture to a smooth

purée in a food processor. Fold the flour, baking powder, raisin mixture and citrus juices into the butter mixture. Divide between the prepared tins and smooth the tops. Bake for 1hr 25min-1hr 30min or until the cakes are risen, springy to touch and a skewer inserted into the centre comes out clean. Cool completely in the tins, covered with a clean tea towel.

4 If you do not have a large enough bowl, make the buttercream in 2 batches. In a very large mixing bowl, beat the butter with a handheld electric whisk until soft. Add ½ of the icing sugar and, starting slowly, beat to combine. Add the remaining icing sugar and the almond extract and beat (slowly at first) until light and fluffy, about 3min. Beat in enough of the milk to make a thick but easily spreadable consistency.

5 Spoon 1.1kg of the buttercream into a separate bowl and set aside. Split the remaining icing evenly among 5 bowls (weigh for best results, each about 250g). Dye each of these 5 icing portions to the desired shade using food gels, then spoon into 5 separate disposable piping bags.

6 Remove the cakes from the tins, peel off the baking parchment and slice both in ½ horizontally with a serrated knife. Spread a little of the reserved plain buttercream on to a cake stand or plate. Using more plain icing, sandwich the sliced cakes back together on the stand/plate, making sure the top layer is a cake base, cut-side down (this will ensure the top of the cake is smooth and flat). Use the remaining plain buttercream to spread a generous layer on top of the cake and a scant layer on the sides. Chill for 20min.

7 Snip 1cm off the end of each piping bag. Pipe a vertical line of seven dots on to the side of the cake, each about 2cm wide and 2cm deep, starting from the top and repeating the colours in the order: yellow, green, blue, purple, pink. Using a separate teaspoon for each colour, smear ½ of each icing dot on to the cake in a horizontal line about 5cm long. On to the smeared icing, pipe another row of vertical dots, starting at the top again with the next colour in the repeated series (eg, green). Smear as before, then repeat the process starting with the third colour (blue), etc. The pattern will become apparent! Repeat the piping and smearing until the cake is covered. There will be a tiny gap where the final row of dots meets your first – make this the back of the cake.

8 Pile the mini chocolate eggs on top of the cake, if using, and serve in slices.

GET AHEAD Prepare to the end of step 3 up to a day ahead. Once cool, remove from the tins, wrap well in clingfilm and store at room temperature. Complete the recipe to serve.

TO STORE The finished cake will keep in an airtight container (or loosely wrapped in foil) at room temperature for up to 2 days.

PER SLICE: CALS 771; FAT 39G; SAT FAT 28G; CARBS 98G

‘For a vibrant effect, swap the pastel gels for bolder colours’