Marbled vanilla cupcakes, vanilla buttercream, fondant mermaid tails decorated with mermaid themed sprinkles.  The perfect Mermaid Cupcakes!

Mermaid Tails

I made these mermaid  tails the night before I made the cupcakes, so that the fondant had enough time to dry. If you make them the same day the fondant might be too soft and the mermaid tails won’t stand up.

I used white ready to roll fondant because that is all I had so I have included the instructions in case you are in the same position and want to dye the food colouring. If you have the correct colour of fondant you want you use, then perfect you can skip straight to the next step.

Related Posts

Vanilla Cupcakes

Vanilla Flower Cupcakes

Spooky Ghost Cupcakes

I always start of by kneading the fondant to make is softer and easier to work with. Once I have done this I then added a small amount of food colouring and continued to knead until the fondant was the correct colour. You can add as much food colouring as you need to get the colour you want. I would always start of small and build up to a brighter colour. If you put too much in to start with then you can’t make the colour lighter.

Next I rolled my fondant out. I lightly covered my worktop using icing sugar but you can use either this or cornflour. Both are great to stop the fondant from sticking and I used a mermaid tail cookie cutter to cut the tails.

I left my mermaid tails blank but at this post you can do any decoration on them you want.

Place the mermaid tails on a flat baking tray and inserted two cocktail sticks into the bottom of the tails and pushed them up into the tails to help support them when they are standing up. I covered the tails and left them overnight.


These cupcakes are so fun to make. The cupcakes are vanilla flavoured and I used three different colours of food colouring and marbled them.  

To make the cupcakes is basically my Velvety Vanilla Cupcake mixture.  I cream together the butter and the sugar until it is light and fluffy. Next I add in the other ingredients and mix until they are all incorporated.

I split the mixture into three bowls and in keeping with the themed decided to dye the cake mixture turquoise, green and purple. I coloured each of the bowls a different colour and then added one spoonful of each to the cupcake cases. 

Next I used a skewer to marble them.  You don’t want to mix the colours so that you end up with a weird browny cake batter, swirling the mixture with the skewer so that they are marbled and the colours are all intertwined works perfectly.

I baked them in the oven for 15-12 minutes until they were golden brown and spring back when I touched them.


To decorate I made a batch of my vanilla buttercream. I mixed together the butter, icing sugar and vanilla extract. When all the ingredients were incorporated and the buttercream was lovely and soft I added in some turquoise food colouring, again I started with a little and gradually added more until I reached the colour I wanted.

The easiest way to add the sprinkles to the cupcakes is to put the sprinkles into a bowl. That way you can then dip the cupcakes into the bowl to cover the entire first layer of buttercream.

I used a Wilton 1M Piping Tip and these large piping bags to pipe the buttercream onto the cupcakes. I started from the middle of the cupcake and piped a swirl of buttercream to the outer edges. Next I dipped the cupcakes into my mermaid themed sprinkles. I used this Mermaid Mix from Iced Jems. This sprinkle mix includes confetti, stars, pearls, 100s and 1000s and also shells and seahorses!

Once the buttercream is covered in sprinkles. I piped a smaller rosette on top. Next I added my mermaid tails and finished with some glitter.


Ready to Roll Icing – I used Dr Oetker Ready to Roll Icing and dyed it turquoise by using food colouring.

Food colouring – The food colouring I use is Pro Gel for these cupcakes I used turquoise, green and purple.

Caster Sugar – I used Silver Spoon

Unsalted butter – For the cupcakes you can use either Unsalted Butter or a baking spread such as Stork. For the buttercream hwoever, you must use unsalted butter. Stork is too soft for the buttercream and it will just end up runny and not pipeable.

Baking Powder – I used Dr Oetker

Vanilla Extract –I used Dr Oetker

Icing Sugar – I used Silver Spoon

Sprinkles –  I used this mermaid mix from Iced Gems

Glitter – I used this blue and pink glitter.


ScalesScales are so important when you are baking. I don’t think I would ever be able to look at the ingredients and know how much was in my bowl. Plus different ingredients weigh different amounts so you may need more/less of to make up the same weight.

Mixing Bowl – I use the mixing bowl that came with my Kitchen Aid but having a mixing bowl big enough for all your ingredients is so important. You don’t want to loose half of your flour because its fallen over the side of the bowl. You can get mixing bowls quite inexpensively from amazon like these plastic ones, and they will last forever!

SpatulaUsing a spatula will mean you can get all the batter around the side of the bowl. Using a wooden spoon for me always leaves some of the mixture behind.

Cookie Cutter – I used a mermaid cookie cutter to cut out the tails.

Cocktail Sticks – I used cocktail sticks to hold my mermaids tails in place. Whatever you use just ensure it is food safe.

Rolling Pin – I used a rolling pin to roll out my fondant but so long as it is round I don’t guess it matters too much what you use, a bottle of the wine from the fridge will roll out your fondant great too.


You could add a flavouring to these cupcakes if you wanted to make them a different colour. I wouldn’t recommend chocolate as then you won’t be able to colour your cake batter.

Mermaid Cupcakes

Sarah Mark
Prep Time 8 hrs 20 mins
Cook Time 20 mins
Decorating Time 30 mins
Total Time 9 hrs 10 mins
Servings 12 Cupcakes


For the Mermaid Tails

  • 200 g Ready to Roll Icing
  • Blue Food Colouring
  • Mermaid Tail Cookie Cutter
  • Cocktail Sticks

For the Cupcakes

  • 145 g Caster Sugar
  • 145 g Unsalted Butter or Stork
  • 3 Large Eggs
  • 1 tsp Baking Powder
  • 1 tsp Vanilla Extract
  • Purple, Green and Blue Food Colouring

For the Decoration

  • 500 g Icing Sugar
  • 250 g Unsalted Butter
  • Food Colouring
  • Sprinkles (optional)
  • Glitter (optional)


To Make the Mermaid Tails

  • I would recommend doing this part the night before you make the cupcakes just so the tails have time to harden slightly. 
  • Line a baking tray with parchment paper and leave to one side.
  • Knead your ready to roll fondant until it is nice and soft. Add a tiny amount of food colouring and continue to knead until the fondant is the desired colour. Alternatively, you could just use a coloured ready to roll icing in which case you will just need to knead it until it is nice and soft. 
  • Roll the fondant out and cut 12 mermaid tails. I used a cookie cutter. The fondant should be quite thick because you are going to insert the cocktail stick into the base of the mermaid tail. 
  • Add the cocktail sticks to the base of the mermaid tails this will help them stand up on top of the cupcakes. 
  • Decorate the mermaid tails. 
  • Pop all your tails onto a flat baking tray and cover. Leave them overnight to harden.     

To Make The Cupcakes

  • Preheat the oven to 180C/160 Fan. Line a muffin tray with cupcake liners and leave to one side. 
  • In a large bowl, whisk together the sugar and butter until light and fluffy. 
  • Add in the flour, eggs, baking powder and vanilla and whisk until all combined. 
  • Spoon the mixture into three separate bowls. 
  • In one bowl add the green food colouring, in the next add purple and in the final bowl add the blue food colouring. Spoon one spoonful of each mixture into the cupcake liners. If you have any leftover you can add this in.Next using a skewer swirl the cupcake mixture so all of the colours are now marbled. 
  • Bake in the oven for 15-20 minutes. You will know the cupcakes are ready when they are golden brown and springy to touch. 

To Make the Buttercream

  • While the cupcakes are cooling make the buttercream. 
  • In a large bowl add the butter, icing sugar and vanilla and mix until it is all combined. Add in a little of the food colouring at.a time mixing in between until you reach the desired colour. 
  • Spoon the mixture into your piping bag and leave to one side. 
  • I found it easiest to pour the tub of sprinkles into a bowl so I could dip the top of my cupcakes into it. 
  • Pipe from the middle of your cupcake outwards until the cupcake is covered in icing. Dip it into the sprinkles and the pipe a small swirl on top. 
  • Add on your mermaid tails and finish off with some edible glitter.

Pin it For Later

If you make any of my recipes use #aspoonofvanilla on social media so I can see all the deliciousness! If you have any recipe suggestions or any comments good and bad about this post and others on my blog, then you can either leave them in the comments section below. You can also find me on InstagramTwitter and Pinterest or you can email me at


  • Brooke

    5 August 2020 at 3:27 pm

    These cupcakes are gorgeous! My daughter would be in Heaven if I had these on her birthday. Can I just pay you to bake them and ship them to me in the US? Lol. So cute.

    1. aspoonfulofvanilla

      17 August 2020 at 11:22 pm

      Thank you! If only I could! haha

  • Nic | Nic’s Adventures & Bakes

    7 August 2020 at 10:26 am

    5 stars
    Thanks for sharing, these look amazing great for a party 🙂

    Nic | Nic’s Adventures & Bakes

    1. aspoonfulofvanilla

      17 August 2020 at 11:21 pm

      These would be perfect cupcakes for a party, for both children and adults!

  • Cue Adulthood

    11 August 2020 at 4:10 am

    5 stars
    This is such a cute and creative idea! I love the design of the cupcake as mermaid tails. Definitely have to try this one out! 🙂

  • Jupiter Hadley

    26 August 2020 at 4:46 pm

    Those tails looked like chocolate – I would have never thought of using fondant! What a smart idea.

Leave a comment

Your email address will not be published. Required fields are marked *

Recipe Rating

Prev Post Next Post
%d bloggers like this: