Crafts & activities

Make a Percy Jackson-inspired cake

Welcome demi-gods! It’s Percy Jackson’s birthday on 18th August, and we’ve baked a special cake to celebrate. Follow our step-by-step instructions and make your own divine dessert!

An image of a birthday cake on top of a yellow zig zag background. The cake has blue buttercream icing and has 'Happy Birthday Percy' written in white icing alongside a blue candle

This recipe makes approximately an 8-inch vanilla sponge cake with a buttercream topping.

You will need:

• Baking or greaseproof paper 

• 4 x 8-inch cake tins


For the sponge cake: 

• 375g butter 

• 450g sugar 

• 6 eggs (room temp) 

• 2 tsp vanilla extract  

• 560g self-raising flour 

• 1.5 tsp bicarbonate of soda 

• 3 tsp baking powder 

• 180g yoghurt 

• 180ml milk 

• Blue food colouring 
For the buttercream topping: 

• 750g butter (soften, leave out the fridge overnight) 

• 1.5kg icing sugar  

• A little milk 

How to make:

1. Pre-heat the oven to 180°C.

2. Cream together the butter, sugar and vanilla until light and fluffy. Add the blue food colouring a few drops at a time, until the mixture is dark blue. 

3. Add the eggs one by one, making sure each egg is combined with the mixture before adding the next one.  

4. Add the flour, bicarbonate of soda and baking powder, and mix.

5. Then, add the yoghurt and milk. Make sure you stir the mixture well.  

6. Line the four 8-inch cake tins with baking or greaseproof paper, then split the mixture equally between the tins.  

7. Pop the cakes in the oven for about 25 minutes (make sure not to leave the oven door open for too long!)  

8. The cakes are done when your kitchen smells amazing or when a toothpick comes out of the centre of the cake cleanly (without any crumbs on it.)  

9. Leave the cakes to cool, then pop them in the fridge to fully chill.  

10. Now on to making the buttercream! Soften the butter, either in the microwave or leave it out of the fridge for around 30 minutes to an hour. Beat the butter with a wooden spoon until it’s very pale in colour (the lighter the colour you can make it, the lighter the buttercream will taste.) 

11. Add the icing sugar to the mixture. We did this in two batches to prevent a big cloud! 

12. Warm some milk in the microwave for 30 seconds and slowly add it in until the mixture has the texture of thick peanut butter. 

13. If you want your buttercream blue (like us and Percy!) add your blue food colouring now.  

To assemble the cake: 

14. Start with one layer of sponge and use a spoon or spatular to spread a layer of buttercream before putting on the next sponge layer. Continue until all four layers of sponge are assembled.  

15. Pop the cake in the fridge for 15 minutes - this will help the cake stay upright and prevent a wonky cake! 

16. After the cake has set, apply a thin layer of buttercream around the edge of the cake. This is your ‘crumb coat’ – it makes sure all the crumbs are set within the buttercream so the final cake is lovely and smooth.  

17. Pop the cake back into the fridge until this layer has set for another 15 minutes. 

18. Now onto the final coat of buttercream! For this layer, you can use as much as you want, and try to get the sides as smooth and straight as possible.

19. Chill the whole cake again and then start decorating! Use whatever you have in your cupboards and fridge to make it beautiful! We used white cake sprinkles and more buttercream! 

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