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This cake is simple in design, but great fun. It’s worth making it over 2 days to allow for jelly to set and fondant to harden. The flavours used are totally up to you; we used vanilla extract as a crowd pleaser, but make it your own –  a handy tip, if you want to flavour your jelly, then you can substitute the water for lemonade. If you want to use flavour extracts, then be sure to use the clear types to avoid discolouring your pool water. 

We used modelling paste to cover the sides of the cake because it sets a little harder than fondant, making it easier to handle and more resilient.

Note: Make sure a grown up helps with small pieces, preparation and baking.

you will need:

for the base

for the icing

For the pool jelly


  1. Start by greasing and lining two 10” x 6” cake tins and preheating your oven to 140c fan.
  2. In the bowl of a stand mixer (or with an electric hand whisk), cream together the butter and sugar until pale and fluffy. Slowly add the eggs one at a time, scraping down the bowl regularly. Lastly, slowly add the flour in batches along with the vanilla extract, being careful not to over mix the batter.
  3. Split the mix equally between the two tins and bake in the centre of the oven for 1 hour. Check to see if the cake is done by inserting a skewer. If it comes out clean then move the tins to a cooling rack for 5-10 minutes, before removing the cakes and allowing them to cool completely. Make the buttercream by whipping the ingredients together until light and fluffy. Add colour cautiously, until you get the desired shade.
  4. Colour your modelling paste in whatever shades you prefer; we used pale blue and grey, but this is your very own cake, so do what makes you happy. We also made some little pool accessories using the modelling paste.
  5. Trim your cakes to get them to a rectangular shape and cut out your pool section. Use a palette knife to cover the sponges in buttercream and refrigerate until set. Melt your white chocolate and colour using the same shade as the buttercream. Once the cake is cool, use a brush or a palette knife to coat the surface where the jelly will sit. This helps the jelly to stick to the cake and stops the sponge going soggy. Keep refrigerated.
  6. Cover your cake board with the green fondant and set aside. Roll out your coloured modelling paste and use a sharp knife (ask an adult to help) to cut the side panels to the correct shape. We had an impression mat to make the design on the tops and sides of the cake, but you can make this by hand using a modelling tool. Set aside to dry.
  7. To make the jelly, bloom gelatine in cold water for 5 minutes and heat your water (or lemonade) to just below simmering. Squeeze the water out of the gelatine and stir this into the hot liquid along with the sugar until dissolved. Allow this to cool to room temperature and then refrigerate until just sloppy.
  8. Re-line the cake tin you used to bake the cake with cling film and lower the cake back in, ensuring it is a snug fit. Make sure the cake and tin are nice and cold, slowly pour in all but a few tbsps of your sloppy jelly and immediately refrigerate. Refrigerate the reserved jelly and then mash up to create texture.
  9. Once the jelly has set, pour over the reserved jelly smash to create water texture and then remove the cling film to reveal your floating swimming pool cake.
  10. Set your cake in the centre of your board. We used royal icing to stick my panels, but you can use some reserved buttercream.
  11. Optional step – Stick the panels to the sides and top of the cake and decorate with fondant accessories and your Bluey characters.