A friend and I made this cake for our other friend’s 30th birthday. And, if I do say so myself, it is pretty epic. There is a long standing tradition of buying each other fish themed gifts, a running joke of sorts, so when it came to deciding what cake to make, we knew it had to involve fish somehow.


When I trawled the internet, I couldn’t find any examples of such a cake to follow. We could find lots of fishy-themed cakes, but surprisingly, there isn’t a Pinterest board for ‘Cakes containing actual real live fish’. There should be. It would be awesome. So after a lot of consideration (and some sketching of ideas) we decided the best way to do it would be to put the fish in a vase in the middle of the cake. Don’t worry, we also provided Casper (the fish) with a nice roomy fish bowl where he now resides after his cake adventure!

The birthday girl absolutely loved it and we had loads of fun making it – we just kept laughing the whole time. Mainly because we were impressed by our own awesomeness. So here’s how we made it.

*Please note, all the links in this post are Affiliate Links, which when clicked on will direct you to Amazon.co.uk. This means that if you click on these links and go on to buy the products, I will receive a small amount of commission.*

What you will need

For the sponge cake:

  • 675g butter (225g per layer)
  • 675g caster sugar (225g per layer)
  • 12 eggs (4 per layer)
  • 3 teaspoon vanilla extract (1 per layer)
  • 675g self-raising flour (225g per layer)
  • 3 teaspoon baking powder (1 per layer)
  • 9 tablespoons of milk (3 per layer)
  • A 12 inch cake tin

For the filling:

  • Jam
  • 400g butter
  • 800g icing sugar
  • Vanilla extract

For the decoration:

Making the sponge cake
We made three layers of sponge cake. As I only had 1 cake tin, we made the cake mixture in three batches, hence why I have split the cake ingredients above into the correct measurements per layer.

  1. Preheat the oven to 180 degrees, and line the bottom of the cake tin with greaseproof paper.
  2. Mix together the butter, caster sugar and vanilla extract.
  3. Whisk in the eggs, adding a little flour if the mixture starts to curdle.
  4. Add the rest of the flour and the baking powder.
  5. Lastly, mix in the milk if needed, to thin out the mixture.
  6. Add to the cake tin and cook for 25-30 minutes. Check with a skewer or knife and if it doesn’t come out clean, bake for a few more minutes before checking again.
  7. Repeat to make all the layers of cake.
  8. Once all the sponges have cooled, place a small bowl or round cutter in the middle of one of the sponges and cut out a circle to make a donut shape. Make sure that your vase will fit in the hole.
  9. Place the donut shaped sponge on top of the other layers of sponge and use that as a guide to cut. This will make sure that the holes are all lined up when you assemble the cake.


Making the filling

  1. Mix the butter, icing sugar and a few drops of vanilla extract together until fluffy.
  2. Sandwich together the layers of sponge cake with jam and butter cream, using a small amount of butter cream on the top layer of sponge (to help the icing stick).

Decorating the cake 

  1. Roll out approx 2kg of blue read-to-roll icing and drape over the top of the sponge.
  2. Smooth out any bubbles or wrinkles, and then use a small knife to neatly cut around the bottom of the cake.
  3. Carefully pierce a small hole in the middle of the sponge cake, and use that to create a cross shape – you can then fold the icing down into the middle of the sponge cake.
  4. 2015-08-29_15.20.38[1]Mix a small amount of icing sugar with water and use that to stick the Smarties around the bottom of the cake, to make the gravel. We used a disposable piping bag to make it a bit neater.
  5. Roll thin strips of green icing into plants, and use these Sea themed Cookie Cutters to make shapes of fish and other sea creatures. We then used a cocktail stick to draw on details, and added a small piece of black icing for the eyes.
  6. Pipe on some of the white icing mixture to make the bubbles.
  7. Shove leftover blue icing and Smarties into your four year old’s mouth because your Husband is about to take her out for a couple of hours and he just whipped you on the leg with a towel and deserves the ensuing hyperactivity. (This step is optional.)

Assembling the cake 

  1. Sterilise the vase by putting it in the dishwasher or wash with hot, soapy water and rinse thoroughly.
  2. Empty the bag containing the goldfish and water into the vase. Only do this when you are ready to present the cake, so that the fish isn’t spending too long inside the vase.
  3. Unveil and then wait ages for the fish to swim above the line of the cake so you can get a photo. And don’t poke it with a long-handled spoon. Just, you know, in case you thought that was a good idea.

*Kizzy, Izzy and Baby is a participant in the Amazon EU Associates Programme, an affiliate advertising programme designed to provide a means for sites to earn advertising fees by advertising and linking to Amazon.co.uk.*


Twinkly Tuesday with Mumma Scribbles 

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