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This delicious mermaid cake has super-moist vanilla layers wrapped in decadent white chocolate buttercream. The blue-green color creates a wonderful aquatic effect when paired with those easy to make but beautiful scales!

An aqua and seafoam green petaled mermaid cake with a piece in the foreground

As many of you know my mom is the bakesperation in my life. So you can imagine how excited I was when she came over for a visit and helped me to make this white chocolate mermaid cake for my niece’s birthday!  I made a two-tone frosting for the inside and the scales to get a more aquatic affect. What do you think??

A blue and green scaled three layer cake

Decoration Notes

  • If you find cake decorating to be a bit intimidating then check out my How to Decorate a Cake post, it has lots of helpful tips and a full how to video.
  • A large round tip is best for piping the scales but I OFTEN use a piping bag with the tip cut off. Try to orient the bag so the seams are on the side of the scale and not in the line of sight.
  • To get the two-tone effect for the scales you need to fill one side of the piping bag with green buttercream and the other with blue. For best effect mix colors that are pretty similar. You can reserve some uncolored buttercream mix the blue and reserve about half to which you will add yellow for the green. You can use the reserved white to lighten either of the colored batches.

a mermaid cake being piped with light blue buttercream

Pro Tips for making this Mermaid Cake

  • If you’re not using 6-inch pans, double the recipe for 8-inch pans or triple the recipe for 9-inch pans.
  • Measure your flour correctly! Adding too much flour to the recipe is the most common mistake. The best, and easiest way to measure flour is by using a scale. If you don’t have one then fluff your flour with a spoon, sprinkle it into your measuring cup, and use a knife to level it off.
  • If you see little clumps of butter after you mix the wet ingredients don’t panic, it all works out by the time you mix in the dry ingredients. You can even use melted butter and warm the milk and sour cream up a bit if you like.
  • You can substitute whole milk yogurt for the sour cream if desired, I do it all the time and can’t really tell the difference.
  • When the cake layers are done you’ll see them pull away from the edge of the pan.
  • Use LOW heat when melting the white chocolate. It is delicious but notoriously easy to burn. Once the chocolate is almost melted through remove from heat and let it sit for a few minutes, then stir.

If you like this cake try some of these recipes!

Blue Ombré Frozen Cake

The Perfect Pink and White Funfetti Cake

White Birthday Cake Recipe

Strawberry Rose Cake

Raspberry Shag Cake

If you’ve tried this mermaid cake recipe then don’t forget to leave a rating and let me know how you got on in the comments below, I love hearing from you!

Mermaid Cake

Author: John Kanell
Servings: 9 people
Prep Time: 40 minutes
Cook Time: 30 minutes
Total Time: 1 hour 10 minutes
A three layer bluegreen cake on a white cake stand
5 from 10 votes
This mermaid cake has super-moist vanilla cake layers wrapped in decadent white chocolate buttercream rendered in easy but beautiful scales.

Ingredients 

For the Cake

  • 1 2/3 cup all-purpose flour 210g
  • 1 cup sugar 200g
  • 1/4 tsp baking soda
  • 1 tsp baking powder
  • 3/4 cup unsalted butter room temperature 170g
  • 3 egg whites room temperature
  • 1 tbsp vanilla extract 15ml
  • 1/2 cup plain greek yogurt 120mL
  • 1/2 cup whole milk 120mL

For the Buttercream:

  • 3 sticks salted butter room temp, 339g
  • 1.5 pounds powdered sugar 680g
  • 1 tbsp vanilla extract 15mL
  • 12 ounces white chocolate 340g
  • 1/4 cup cream 60mL
  • Food coloring if desired

Instructions

For the buttercream

  • Melt the white chocolate and cream together at very low heat, set aside.
  • Beat the butter until light and fluffy, add the sugar a cup at a time and beat well. Drizzle in the white chocolate and beat until combined.
  • Separate the buttercream into 2 equal batches and color two of the batches with blue and green food coloring in different shades of the scales.

For the Cake

  • Butter and flour 3 six-inch cake pans. Preheat oven to 350F
  • Sift the dry ingredients together in a large bowl.
  • Mix the wet ingredients (including the sugar) together in a medium bowl.
  • Add the wet to the dry and mix until just combined.
  • Divide the mixture into 3 6″ cake pans that have been buttered and floured.
  • Bake at 350 for about 25-30 minutes or until the centers are springy to the touch.

For the Assembly

  • Pipe rings of the green and blue buttercream onto the first layer then cover with the second layer. Repeat step.
  • Cover cake in a thin layer of buttercream and give a rough smooth.
  • Place green and blue buttercream in a piping bag fitted with a large round tip. Pipe the petals by swiping up with the tip.

Notes

  • If you’re not using 6-inch pans, double the recipe for 8-inch pans or triple the recipe for 9-inch pans.
  • Measure your flour correctly! Adding too much flour to the recipe is the most common mistake. The best, and easiest way to measure flour is by using a scale. If you don't have one then fluff your flour with a spoon, sprinkle it into your measuring cup, and use a knife to level it off.
  • If you see little clumps of butter after you mix the wet ingredients don’t panic, it all works out by the time you mix in the dry ingredients. You can even use melted butter and warm the milk and sour cream up a bit if you like.
  • You can substitute whole milk yogurt for the sour cream if desired, I do it all the time and can’t really tell the difference.
  • To get FLAT layers that are moist inside and out try using cake strips! You can buy a set on the shop page or make your own from foil and paper towels at home. I made a whole blog post on it so check it out if you’re interested!

Nutrition

Serving: 79g Calories: 330kcal Carbohydrates: 43g Protein: 3g Fat: 17g Saturated Fat: 6g Trans Fat: 2.5g Cholesterol: 30mg Sodium: 310mg Fiber: 0.5g Sugar: 30g Vitamin A: 100IU Calcium: 40mg Iron: 1.4mg

*Nutrition Disclaimer

Course: Dessert
Cuisine: American

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