Mermaid cake decoration how to diy fondant pastel inspiration

Mermaid Cake

A birthday party is not complete without a beautiful cake! If it’s a mermaid themed party you’re having, you’ll need a mermaid cake to go with it! You may be able to find one at your local grocery store or a bakery, but perhaps not. Maybe you’d like to try your hand at making one yourself!

This article will provide you with a delicious vanilla cake recipe, and give instructions and ideas for making the perfect mermaid cake!

There are so many different ways to make a cake be mermaid-esque. It’s all about the colors you use, the frosting method, and the candy and décor you use. Keep reading for lots of mermaid cake inspiration!

Mermaid cake pastel mermaid tail decorations

Mermaid cake recipe

Little mermaid cake

Mermaid cake with barbie doll

How to make mermaid tail for a cake

How to make mermaid scales on a cake

Mermaid cake topper

Ocean cake base

Mermaid cake decorations

Mermaid cake fondant decorations

Mermaid scales cake decoration birthday

Mermaid cake recipe

This vanilla cake recipe is such a crowd pleaser! It is a dense and flavorful cake, almost like pound cake but lighter.  Here are the ingredients you will need:

  •         1 ½  sticks of butter
  •         2 cups of sugar
  •         1 tsp of vanilla
  •         A dash of salt
  •         2 ¼ cups of flour
  •         2 tsp of baking powder
  •         1 cup of buttermilk
  •         3 eggs


  1.       Cream together the butter and sugar in a mixer.
  2.       Mix in your eggs one at a time.
  3.       Add vanilla.
  4.       In a separate bowl, sift together the flour, baking powder, and salt.
  5.       Alternate between adding the flour mixture and buttermilk, mixing the flour in first and last.
  6.       Mix on medium speed until everything is well combined.
  7.       Grease around two 8inch pans.
  8.       Pour the cake mixture into the pans and bake at 350 degrees for about 25 minutes, or until you can stick a toothpick in the cake and have it come out clean.

You can’t decorate a cake without frosting!

Here’s a delicious frosting recipe from Two Sisters Crafting.

  •         4 cups Powdered Sugar (or 1 pound)
  •         1 cup Butter (Softened Salted Sweet Cream)
  •         2-3 teaspoons Vanilla
  •         1-2 tablespoons Milk

Once you have the cake layers baked and cooled and the frosting is made, you can begin assembling them into a cake!

You will need a surface for the cake to sit on. It could be a large plate or a ten inch cake board. A cake board can be purchased at a craft store.

The cakes will likely be domed at the top. You will need to cut off this dome so the cake surface is flat.

Smear a little bit of frosting onto the cake board to make sure the cake will not slide around. Place the first layer of cake on carefully, making sure to keep it centered. Add a generous layer of frosting in between. You can add anything you want to the inside of the cake. A layer of fruit preserves tastes delicious.

Add your second layer of cake.

Next step is to crumb coat and chill the cake. To do this, you need to give the cake a thin coat of frosting all over and use a cake decorating spatula to smear it against the cake, trapping in all the crumbs. Let sit in the fridge until you can touch the frosting and none comes off.

You can skip that part if you want, but you may end up with a cake with crumbs all over it, which doesn’t look as nice.

Next your cake is ready to decorate!

Mermaid cake blue pink mermaid tail shells

Little mermaid cake

You could make a Little Mermaid cake using an Ariel doll or topper, or you could sculpt a little Ariel out of fondant. You could also get a sheet cake with a photo printed onto it of a scene from the movie.

Here are some examples:

Little mermaid cake photos

little mermaid cake triton ursula 3 layers wedding

Tsunammi cake Ariel princess

Mermaid cake with barbie doll

A common mermaid cake idea is to have a doll sitting on top of the cake with a long beautiful tail cascading down the cake. You can use a mermaid doll or use the torso of a regular doll and make the tail out of frosting.

The best cake shape for this mermaid cake is a dome. So you will have to do some carving.

If using a regular doll with legs, first you want to wrap saran wrap around the legs. Then you want to make a small incision at the top center of the cake. Insert the doll’s legs into the cake and leave from the waist up outside of the cake.

Next, frost the whole cake with blue frosting. You can do varying colors, patterns, or textures.

Then you will use either frosting or fondant to make the tail. For a frosting tail, use a round tip to pipe on individual scales. For a fondant tail, sculpt out the tail and place it at the base of the mermaid doll.

Add any extra decorations like sprinkles, pearl candies, frosting decorations or fondant decorations. See the lower section for more on mermaid cake decorations.


How to make mermaid tail cake

To make a mermaid tail shaped cake you will need three 6 inch cakes, each about two inches tall.

Smear a little bit of frosting onto a cake board to make sure the cake will not slide around. Place the first layer of cake on top carefully, making sure to keep it centered.

Add a generous layer of frosting in between. You can add anything you want to the inside of the cake. A layer of fruit preserves tastes delicious.

Repeat with the second and third cake layer, then put it in the fridge to chill for about half an hour.

After it has chilled for half an hour it is time to carve the cake into a mermaid tail shape.

You will need a long, serrated cake cutting knife. Start from the top of the cake and shave off some layers of cake. The most cake will be taken from the top of the cake, which you want to come to a thin point. The whole cake should look like a cone.

You will next need to add some scales to the cake. See the section below to find out how to do that.

Once you have the cake covered in mermaid scales, you will need to add a fluke on top! A mermaid tail isn't complete without a tail fin! To make a fluke you can sculpt one out of fondant or have a picture cut out. Attach a skewer or toothpick to the fluke so that you can stick it into the cake and it won’t be able to fall off.

Mermaid tail cake how to make

How to make mermaid scales on a cake

There are two different methods to make mermaid scales on a cake. You could use fondant or frosting.

Frosting scales

How to frosting mermaid scales  on a cake

You will need a frosting bag with a coupler. With just the coupler and no frosting tip you can pipe a nice circular dab.

Starting at the bottom of the cake squeeze the cake bag until a little circle of frosting comes out and then release pressure as you pull it upward.

Next take an offset spatula to flatten the frosting dab and pull upward. Go all around the cake doing this. Continue as you get to the top, going around in a circle.

When you get to the very center of the cake you will only have space to add one scale. Sometimes the center can look a little messy so it’s a good idea to have a cake topper!

Fondant scales

fondant mermaid scales how to cake bakery skilss purple blue

Fondant is made of sugar, water, gelatin, vegetable fat or shortening, and glycerol.  It is essentially edible modeling clay! You can make individual scales out of fondant to layer around the cake in a scale pattern.

You can use whatever colors you like! You can also get creative with it and use multiple colors or shades of a color. Green and teal look good together, or varying shades of blue. You can buy fondant already colored or use gel food coloring.

To color the fondant, add a drop of the color of your choice to the fondant. Fold it in half several times and then just knead it until the color incorporates fully into the fondant.You may have to add a few more drops to get it to the desired color.

Roll out the fondant to 1/8th of an inch thick. Use a circular cookie cutter to cut out the scales.

The cookie cutter should be about 1 ½ inches in diameter. You will probably need at least 50 scales.

Starting at the bottom, place the scales in a row around a frosted cake. Make sure each row of scales covers the top of the row beneath it. Go around until you get to the top.

Mermaid cake topper

A cake topper really seems to complete a cake! For a mermaid cake topper you may go for a mermaid tail sticking out of the cake, a whole mermaid, the birthday child's name with or something with the birthday child's name on it. Also common for a mermaid cake is a seashell topper. There are paper toppers which are 2d and come on a little stick. There are also 3d cake toppers such as a fondant mermaid sculpture, or a mermaid candle.

Mermaid cake topper decorations signs name

Where to get a mermaid cake topper:

Buy one at the store

If you go to your local craft store or party store you will likely be able to find a mermaid cake topper.

Order one on Etsy

You can find some beautiful options for mermaid cake toppers on Etsy. There is so much variety. You can even have a custom made topper with the name of the birthday child. It’s good to shop on Etsy because you can support artisans and small businesses!

Print out picture

Here’s a super easy option for a mermaid cake topper. Find a picture you like and print it out, then tape a skewer to the back of it. You could also create your own design by using Canva. If you go that route, you can make it super customized with the birthday child’s name and age!

Draw one

If you are the artistic type, you could consider drawing or coloring a cake topper onto card stock and cutting it out and taping a skewer or toothpick to the back of it.

Make one out of fondant

Mermaid tail diy home made fondant decoration sea shells cake toppings decorationsMermaid tail topper decoration fondant cake

Making a fondant cake topper is not too difficult. You could use a mold or you could sculpt one yourself. Most craft stores have a cake decorating section where you will be able to find some fondant and a mermaid mold. If you can’t use a mold, sculpting one is not too difficult. You can go for a simple mermaid tail topper. For a 3d topper, simply create three pieces with the fondant. Make a cone shaped piece, and two teardrop shaped pieces. Attach the two teardrop shaped pieces to the thin end of the cone to form the fluke. Use a toothpick to carve some fin lines on the fluke. To make scales you can use a straw to press against the fondant at an angle to create, so that you get a scale shape and not circles.

Ocean cake base

A mermaid topper and mermaid decorations are one part of decorating a mermaid cake, but the most important thing is the base of the cake. This is the way you frost it before adding the complimentary details.

There are many styles for frosting a cake. Some are very simple and can be done by a beginner, some are a little more advanced. 

Beginner friendly:

One color base- Choose your frosting color and smear frosting onto the cake, coating the sides and top with a 1/4th inch thickness. Use your offset spatula to spread the frosting around to evenly disperse the frosting. Then take an offset spatula and gently go around the cake, spatula flat against the cake. Apply light pressure as you spin the cake on a turntable or lazy susan. This creates a nice smoothly frosted cake.

Textured base- Using a color palette of your choice, smear on your frosting. It can be one color or you could add splotches of various shades all over the cake. Next you want to take your offset spatula and go around the cake pushing the frosting around to create a choppy texture that resembles rough ocean waves.

Ombre cake- An ombre cake is when the cake starts as one color at the bottom and gradually fades into different colors up to the top. These are lovely with lighter shades of blue, green, white, and purple. All you do is smear individual stripes of varying colors onto the cake, then take an offset spatula and gently go around the cake smoothing it until the colors blend together. Use a turntable to get a nice smooth cake.


Rosettes- Piping beautiful rosettes around a cake makes for a stunning cake. Rosettes are made by using a star tip and making little swirls that end up looking similar to roses.

Rosettes Piping beautiful mermaid cake teal purple green turquoise

Fondant- Fondant is difficult to work with for a beginner, but if you are up for the challenge, give this a try! You could cover a whole cake in fondant instead of frosting, or you could make fondant scales. See section above on how to do that.

Fondant scales frosting cake mermaid green design

Mermaid cake decorations

Here are some elements you can use to decorate your cake:

Sparkly sprinkles- There are sparkly sprinkles that look very much like glitter. Mermaids are associated with sparkly things because of their glimmering tails and the twinkle of the ocean. Using sparkly sprinkles really adds a magical touch to your mermaid cake. You can usually find some at the grocery store.

Pearl candies- Beautiful, opalescent pearls are abundant in the ocean. It just makes sense to use pearly candies on your cake. You can buy them at a craft store cake decorating section. They are either small candy coated chocolates, or crunchy sugar beads. Either way they are very shimmering and look like real pearls.

Flowers- You can use specific frosting tips to make some lovely little sea flowers. Use colors like pink and yellow.

Seaweed- A leaf tip will allow you to make seaweed. Using frosting dyed green with gel food color, pipe little strands going up the cake. You can also make seaweed with fondant. Just roll out thin green strips of fondant and twist them into spirals.

Swedish fish- The ocean’s not complete without some fish! Swedish fish make a great decoration because they are convenient, realistic, and delicious! You can save time by using Swedish Fish rather than making your own.

White chocolate seashells- These require a little bit of work, but they look so good and are tasty! You will need a seashell shaped candy mold. Heat some white chocolate candy melts over a double boiler. Mix frequently until they melt. Then spoon little bits of the chocolate into the candy mold. Refrigerate them until they are hardened, then you can use them on your cake.

Mermaid cake decorations

Mermaid cake fondant decorations

Some good decorations to make out of fondant are seashells, seaweed, fish, mermaid tails, and other aquatic animals.

Sculpting your own decorations is a fun way to bring the ocean to your cake! You could free hand sculpt your decorations or use a mold. See the section above for instructions on making a mermaid tail out of fondant.

Seashells are not too difficult to make. Follow the steps in these images below to make a conch shell, scallop shell, and auger shell out of white fondant. Here is a video demonstration.

To make the conch shell, simply roll out a thin tapered tube of about four inches of fondant. Start from the thinner end and begin rolling. Shape the end of the shell to look more like the open side of the conch. Press your finger into the flat end.

conch fondant sea shell sculpture tutorial diy

For the auger shell, roll out four fondant balls, decreasing in size. For the tip of the shell make a little tear drop shaped piece. Push the pieces together, like assembling a tiny snowman. Begin rolling the whole thing out to make the pieces come together more. Press your finger into the wider end and make an indentation to resemble the opening of the shell.

auger shell fondant cake decoration mermaid sea ocean

Roll out five-inch-long teardrop shaped pieces. Place the thinner ends together, side by side, and mold them to come to a point. Work with the fondant to bring the shell to a triangular shape. Flatten the top a little to make the wider end come together more. Add two little triangular shaped pieces at the bottom.

Mermaid shell decoration cake fondant tutorial diy

Here is another good example of a cake with fondant decorations. It includes little strands of seaweed, an octopus, fish, shells, and a starfish on a simple blue frosted cake.strands of seaweed, an octopus, fish, shells, and a starfish on a simple blue frosted cake. mermaid


A unique ocean jelly cake that you can add mermaids. Island cake with Jello.

Whether you’re planning to make your own cake or just use this article as mermaid cake inspiration, we hope you enjoyed it! Have a magical mermaid party and a FABULOUS cake!

Speaking of mermaid parties, did you know you can hire a professional mermaid to perform for the kids in a realistic mermaid tail? A professional mermaid brings that extra spark of magic! You can click here to be connected with one! She can lead “happy birthday” and even cut the cake. A professional mermaid at a kid’s party really tops the cake!


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