Trend alert: Mermaid Cake

Charlotte White from Restoration Cake guides you through creating an on-trend mermaid cake – a glamorous swish of a tail under the sea covered in sparkles.

Brought to you by Restoration Cake


You would have to have been living under a rock not to have noticed the trend for all things mermaid-inspired currently sweeping the globe. Much like the cult of the unicorn, the mermaid trend revolves around all things pastel-coloured and sparkly with a slight difference in colour palette, the only feature to distinguish one from the other. When thinking mermaid, expect seafoam greens, pinks and purples, iridescent scales and shell details, and a healthy serving of glitter. The ‘unicorn cake’ has taken the internet by storm – this simply covered cake, decorated only with a pair of fluttering eyelashes and topped with an elaborate horn (please take all aforementioned glitter, sparkles, and the colour palette as read) has created quite the sensation. My own homage to this design, with a mermaid in mind, could provide an alternative solution for those lacking the time or patience to wait for a modelling paste unicorn horn to dry. My mermaid’s tail curls effortlessly around my cake with minimal drying time required, and affords the option for little helpers to get involved with its painting. How fun to paint your very own mermaid’s tail! A sprinkling of gorgeous Sprinkletti sprinkles makes this cake fit for any party.

Mermaid Cake by Charlotte White from Restoration Cake

You will need:

For the cake:

  • 20cm (8in) cake tier, mounted on a 20cm (8in) cake drum and covered in seafoam coloured sugarpaste ( I used Bluegrass by Squires Kitchen)

To decorate:

  • Cake Lace pearl lustre dust
  • edible glaze (I used Dinkydoodle Designs Liquid Shiny)
  • buttercream coloured using Bluegrass by Squires Kitchen
  • ‘Party Mix’ sprinkles by Sprinkletti
  • ‘Frozen’ Mix large sugar pearls by Purple Cupcakes
  • Rice Krispie Treats (I used 6x 28g (1oz) bars)
  • 250g (9oz) white sugarpaste
  • 100g (3½oz) Carlos Lischetti modelling paste
  • scale tools (large, medium and small arc tools from Sweet Elite at The Cake Decorating Company)
  • dust colours (I used Roxy & Rich Turquoise, Teal, Violet, Burnt Amethyst, and Honeydew)
  • clear alcohol or lemon juice EQUIPMENT
  • 25cm (10in) cake drum covered in seafoam coloured sugarpaste
  • paintbrushes
  • shell silicone moulds from Great Impressions by Squire’s Kitchen (Prickle Cockle and Triton)

Stage 1: Cover the cake, create and attach the tail

  1. Begin by covering both your 20cm (8in) cake and 25cm (10in) cake drum in seafoam coloured sugarpaste. Bluegrass by Squire’s Kitchen gives a lovely shade when used sparingly. Allow to dry before mounting your cake on the covered drum, securing with a little royal icing.
  2. Rice Krispie treats, whether shop-bought or homemade, make the perfect modelling material. To make the mermaid’s tail, begin by taking 6 Rice Krispie treat bars and moulding them into the shape of a tail – thicker at one end and tapering off to a point at the other end.
  3. Roll out sufficient white sugarpaste to wrap around the tail shape.
  4. Smooth the sugarpaste around the tail, creating a flawless finish with a seam along one edge.
  5. Insert two bamboo skewers into the top of the cake, trimming so that they stick 5cm (2in) up from the surface.
  6. Pipe a line of royal icing along the seam up the back of the mermaid’s tail.
  7. Push the wider edge of the tail onto the bamboo skewers to tether it to the cake.
  8. Begin to manipulate the tail around the cake, starting with the wider edge at the top edge of the cake and curving the point of the tail around to the halfway point of the cake. The tail should be strong enough to hold its shape and its movement around the cake. Focus on sticking the side of the tail with the royal icing to the side of the cake to conceal the join.

Stage 2: cutting and painting the fin

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  1. Use a template to create fins for the mermaid’s tail. Roll out some modelling paste to 3mm thickness and cut out the shape using a craft knife. Set aside to dry.
  2. Once dry, use edible food paints to paint the fin of the mermaid’s tail. I have used violet for this as I felt that this contrasted the most effectively with the seafoam sugarpaste. Allow to dry.

Stage 3: painting the tail

  1. Add texture to your mermaid’s tail using scale tools. I have used two different sizes from Sweet Elite starting with medium scales at the wider base, moving to small at the tapered end of the tail. Scales should be marked in rows.
  2. Now for the fun bit! Add colour to your mermaid’s tail by painting each scale with edible paint made from food dust colours. I have used turquoise, teal, violet, burnt amethyst and honeydew, trying to break up all of the colours to create a rainbow of sparkling scales.
  3. Once dry, pipe a little royal icing onto the back of the fin and gently press onto the surface of the cake. Hold it in position for a few moments and it should hold just fine.

Stage 4: making the shells  

  1. Use modelling paste pressed into silicone moulds to shape sufficient sugar shells to run around the base of your cake. Allow your shells to dry.
  2. I painted my cockle shells using pearl lustre mixed with a small amount of turquoise colour. Edible glaze makes this into a shiny edible paint. I repeated this process with my larger Triton shells using pearl lustre with a little teal. Prepare a basic buttercream using 2 parts icing sugar to 1 part unsalted butter and a generous splash of the best vanilla extract that you can afford. Remember that the key ingredient in a great buttercream is air, so whip that buttercream until it is smooth and heavenly. Colour up using a professional quality food paste. I used Bluegrass by Squires Kitchen to get this seafoam shade.

Stage 5: pipe the swirls

  1. Load the buttercream into a disposable piping bag fitted with a large open star nozzle (the kind that you would usually use for cupcakes). Pipe swirls, rosettes and kisses, around the top of the cake to conceal the point where the wide base of the tail joins the cake.

Stage 6: final decorative touches

  1. Sprinkle the top of the cake, including the piped details, with beautiful sprinkles. Go for it. You deserve it. I used giant sugar pearls and a fantastic colourful sprinkle mix by Sprinkletti.
  2. Adorn the base of the cake with your painted shells. I stuck these to the cake with a little royal icing.
  3. Wrap double-sided tape around the edge of your cake drum. Remove the protective strip and run a hot pink ribbon around the edge, securing at the back with a little extra tape.
  4. Your cake is now the perfect centrepiece for any Under the Sea themed party!

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