Updated: Apr 21, 2022
There is nothing more nostalgic than a jelly pool cake. Especially for us 70's/80's/90's born babies. This one has jelly set inside the cake- which makes it a bit of show stopper, and it really does have the coolest cross section when cut into slices. The process is a bit fiddly, but it's an enjoyable cake to put together- just give yourself plenty of time with all the finishing touches. It will make the process so much more fun.
The jelly needs a good few hours to set properly, so it's a good idea to make your cake the day before and start the decorating. You can even pre-ice your cake the day and start the jelly first thing.
B E F O R E Y O U S T A R T , Y O U ' L L N E E D :
(many of the pool accessories are just an idea, we used what we had on hand- but feel free to get creative with what you can rustle up!)
- an 8" double layered cake
- buttercream icing and blue spirulina powder (or food colouring will work too!) Once your icing is ready, add enough colour to make a light blue colour- go easy for starters, you can always add more)
- powdered gelatine, lemon juice and sugar to make the jelly (alternatively, a packet of blue jelly, you'll need to add extra gelatine to this too)
- red licorice straps or flat colourful biscuits that can be shaped into towels
- black licorice straps cut into small squares for tiles
- paper umbrella (or one halved orange + red licorice log and a toothpick for umbrella stand)
- sour ring lollies to use as life rings
- lollipops, cotton and small triangle stickers for the flags
- any sweets, flowers, greenery, people etc you think you'd like to add to your cake.
F I R S T U P , M A K E T H E J E L L Y :
For an 8" sized cake, you'll need approximately 350ml jelly for your pool. This recipe makes 500ml of jelly, which means you've got a bit extra in case you decide make your pool a bit bigger.
100ml hot (not boiling) water
5 tsp powdered gelatine
1Tbsp lemon juice, strained
1/3 cup caster sugar
400 ml water
blue spirulina powder or food colouring, as required
1. Measure 100ml of hot water into a small bowl or jug. Stir well and leave gelatine to dissolve.
2. In a small saucepan, place lemon juice, sugar and water and stirring frequently and bring to a gentle simmer.
3. Once sugar has dissolved, remove from heat and mix in food colouring- once again, go easy for starters!
4. When lemon juice mixture has cooled down to a warm temperature, add your gelatine mixture and stir through gently until you can see that all gelatine has incorporated into mixture. Set aside somewhere at room temperature and leave to cool (stirring when you remember to, as you don't want it to cool completely and set).
*you can also use a blue 85g packet jelly for this step- just pour empty the contents of your jelly box into a bowl, and mix through an extra 1 1/2 tsp powdered gelatine. Pour over 500ml boiling water, stir until jelly powder has dissolved and then set aside somewhere to cool.
T O A S S E M B L E T H E C A K E :
1. Set aside 1/2 cup of buttercream from your mixture and cover (this is to ice the inside of your cake).
2. Place some buttercream on bottom cake and spread over evenly. Gently put top cake in place, and then spread a layer of buttercream over the top and sides.
3. Put cake in fridge to set.
4. Once icing has set, carefully measure out approximately 3cm from the edge of outside edge of cake and cut down to the depth of first cake. Then make an X across centre piece of cake and gently extract the middle, leaving the middle layer of buttercream at the bottom.
5. Ice bottom of pool and the sides with remaining buttercream, making sure that all the cake is covered and the pool sealed (so that it will hold the jelly without leaking).
6. Return to fridge and leave cake until icing is well set.
7. Check jelly to make sure it is cool (if it is too hot, it will melt the buttercream which is not ideal!). Gently pour jelly into pool until it is full, and place in fridge to set for a few hours.
8. While you're waiting on jelly, you can put together some pool accessories- we made an orange umbrella (a small orange sliced in half for the umbrella and a raspberry licorice log (strengthened with a toothpick to hold it up in the cake)), raspberry licorice straps iced with vanilla icing stripes to make towels, life rings with icing stripes, black licorice squares with white icing between to make tiles). You can go wild here!
9. We also cut small triangles from red stickers and stuck them onto cotton thread to make swimming flags, and then tied them between 2 lollipops. We also used some small yellow fimo beads we had made for a previous pool cake as lane markers to place around the edge of pool- but you could do this with small colourful lollies)
10. Once jelly has set, place the accessories around pool. This is the best part, so make sure you've got time to enjoy setting it up.
11. Enjoy! Best stored in a cool place (cool room temperature is okay) prior to serving. Avoid hot temperatures (or place in the fridge if it gets too hot) as jelly holds better together when cool.