Rainbow piñata birthday cake

“This cake is pure, unadulterated childish glee. There’s no holding back. It’s full colour, full sugar, then full throttle post-ingestion. And I have to say, it’s as much fun to make as it is to give! I guarantee you’ll have as much fun making this as the recipient has cutting it! I mixed popping candy in with the sprinkles before coating the cake for extra fun.” Poh Ling Yeow, Poh & Co. 2

• serves

  40

• prep

  1:30 hour

• cook

  30 minutes

• difficulty

  Mid

Ingredients

• 900 g (6 cups) plain flour, sifted
• 650 g (3 cups) caster sugar
• 1 ½ tsp salt
• 3 tsp bicarbonate of soda, sifted
• 750 ml (3 cups) milk
• 180 ml (¾ cup) white vinegar
• 6 eggs, lightly whisked
• 3 tsp natural vanilla extract
• 600 g unsalted butter, melted and cooled (see Note)
• 1–2 tsp each of 6 colours of food colouring (see Note)
• 1½ cups mixed sprinkles of choice
• 4 cups small mixed chocolates or lollies of choice

Frosting

• 750 g cream cheese, at room temperature
• 150 g butter, at room temperature
• 400 g (2½ cups) icing sugar, or to taste
• 2 tsp natural vanilla extract

You will need 6 x 20cm cake tins for this recipe.

Instructions

Grease only the sides of 6 × 20 cm diameter cake tins with butter (see Note), then coat thoroughly with flour. Trace around the base of each tin with baking paper, then cut out and use to line the base of each tin.

Preheat oven to 180˚C (160˚C fan-forced).

Place the flour, sugar, bicarbonate of soda  and salt in a large bowl and whisk briefly to combine. Place the milk and vinegar in a jug and leave for 30 seconds to bubble. Add the vinegar and milk mixture, egg, vanilla extract and melted butter to the flour mixture, then whisk until the mixture is combined to form a smooth batter.

Using a measuring cup, divide the batter evenly among 6 bowls. Whisk food colouring of choice into each bowl to the desired intensity of colour, then transfer 1 of the different-coloured batters into each of the prepared tins.

Bake for 30 minutes or until a skewer inserted in the centre of each cake comes out clean. Carefully remove the cakes from their tins and cool completely on wire racks before using.

To make the frosting, using a stand mixer fitted with the whisk attachment on medium–high speed, beat the cream cheese, butter, icing sugar and vanilla extract until smooth.

To prepare 5 of the cakes for stacking, carefully slice off the domed part of each of the 5 cakes to create a flat surface; leave the sixth cake intact as it will form the top layer. Stack the coloured cake layers in the order you like, setting the top layer aside. Using an 8 cm-diameter pastry cutter, carefully cut a circle from the centre of the 5 cake layers, leaving the top layer intact. Set the cut-out circles aside to use later.

To assemble the cake, place the first layer on a serving platter or cake board. Spread a thin layer of the frosting on top, making sure to leave a 5 mm border around the cut-out edge of the inner circle. Repeat with the remaining cake layers and more frosting, then, before adding the final layer (with no hole cut from it), pour your mixed chocolates or lollies into the hole.

Spread a thin layer of the frosting over the entire surface of the cake. Place the iced cake in a large, clean cardboard box or on a tray and gently cup the sprinkles against the edge so they stick to the frosting. Repeat this until the sides of the cake are covered well.

To cut out letters or numbers (if using), slice each reserved coloured cake circle in half widthways through the centre to form 2 layers. Using a paring knife, carefully cut out the letters or numbers required. Insert toothpicks or skewers in the base of the letters or numbers to add stability and a variety of heights; these also enable you to secure the letters or numbers to the assembled cake.

When cutting the cake, make sure a fair-sized wedge is cut and removed to give the chocolates or lollies room to tumble out of the cake nicely, then proceed with cutting the remaining slices. Serve. 

Note

• You can use liquid or gel food colourings in this cake. If you use only liquid colourings then you will need to use the full 600g of butter to ensure colour depth. If you use gel colourings,  500g of butter will be enough in this recipe. 

• When it comes to the food colouring, for the artistically challenged, mixing mostly red with a little blue makes purple, mostly yellow with a little red makes orange, and  mostly yellow with a little blue makes green. Make sure you don’t overcook the cakes as the intensity of the food colouring will fade as the cakes brown more. 

• It is important to use six tins that are exactly the same and to divide the batter evenly among them so they six layers cook in the same amount of time and are the same size.

• If your oven is not large enough to cook all the cakes at one time, bake three tins on the middle shelf, then, when they are cooked, bake the remaining three cakes – don’t worry, as this batter is very forgiving and the ones waiting to be baked will not be affected.

Photography, styling and food preparation by china squirrel.

Poh & Co. 2 Thursdays at 8.30pm on SBS.

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Cook's Notes

Oven temperatures are for conventional; if using fan-forced (convection), reduce the temperature by 20˚C. | We use Australian tablespoons and cups: 1 teaspoon equals 5 ml; 1 tablespoon equals 20 ml; 1 cup equals 250 ml. | All herbs are fresh (unless specified) and cups are lightly packed. | All vegetables are medium size and peeled, unless specified. | All eggs are 55-60 g, unless specified.