Purple and Blue Buttercream Mermaid Scales Cake

If you’ve ever dreamed of making a stunning mermaid-themed cake but worried it might be too tricky, this Purple and Blue Buttercream Mermaid Scales Cake is the perfect DIY option. With just a few simple piping techniques, you can transform an ordinary cake into a whimsical, ocean-inspired masterpiece. The best part? You don’t need to be a pro baker to pull it off

Whether you’re celebrating a birthday, a beach-themed party, or just want to try something fun in the kitchen, this cake is sure to impress. The buttercream scales in shades of purple, pink, and blue create a mesmerizing look that’s surprisingly easy to achieve. Let’s dive right in and make this magical mermaid cake

this Recipe

Why You’ll Love This Recipe

Key Benefits

• Easy enough for beginners but looks professional
• Customizable colors to match any theme
• Perfect for birthdays, celebrations, or a fun weekend baking project

Taste & Texture

This cake is soft, fluffy, and pairs beautifully with the creamy buttercream. The frosting is smooth with just the right amount of sweetness, and the different colors add a fun visual appeal

Dietary Attributes

This recipe can be made gluten-free or dairy-free with a few simple substitutions, which are included below

Ingredients & Substitutions

For the Cake

• 2 ½ cups all-purpose flour (or gluten-free 1:1 baking flour)
• 2 ½ tsp baking powder
• ½ tsp salt
• 1 cup unsalted butter, softened
• 2 cups granulated sugar
• 4 large eggs
• 1 tbsp vanilla extract
• 1 cup whole milk (or almond milk for dairy-free)

For the Buttercream Frosting

• 1 ½ cups unsalted butter, softened
• 5 cups powdered sugar
• 2 tsp vanilla extract
• 3-4 tbsp heavy cream (or dairy-free alternative)
• Food coloring: purple, blue, and pink

Possible Substitutions

• Swap out vanilla extract for almond or coconut extract for a unique flavor
• Use store-bought cake mix for an even easier version
• Dairy-free butter and coconut milk work great for a lactose-free alternative

Step-by-Step Instructions

Step 1: Bake the Cake

1. Preheat your oven to 350°F (175°C). Grease and line three 8-inch round cake pans
2. In a medium bowl, whisk together flour, baking powder, and salt
3. In a large mixing bowl, beat butter and sugar until light and fluffy. Add eggs one at a time, then mix in vanilla
4. Alternate adding the dry ingredients and milk, beginning and ending with the dry mix. Mix until just combined
5. Divide the batter evenly into the prepared cake pans and bake for 25-30 minutes or until a toothpick inserted in the center comes out clean
6. Let cakes cool completely before frosting

Step 2: Make the Buttercream

1. In a large bowl, beat the softened butter until smooth and creamy
2. Gradually add powdered sugar, mixing well after each addition
3. Add vanilla extract and heavy cream, beating until fluffy and smooth
4. Divide the frosting into three separate bowls and tint each one with purple, blue, and pink food coloring

Step 3: Assemble & Crumb Coat

1. Level your cake layers if needed, then stack them with a thin layer of buttercream between each layer
2. Apply a thin crumb coat of buttercream over the entire cake to seal in crumbs. Chill for 30 minutes

Step 4: Create the Mermaid Scales

1. Fit piping bags with round piping tips and fill each with a different color of frosting
2. Pipe small dots in rows, then use the back of a spoon or an offset spatula to gently press and drag each dot to create a scale effect
3. Repeat with alternating colors until the entire cake is covered

Expert Tips & Tricks

Best Practices

• Use gel food coloring for vibrant shades without affecting frosting consistency
• Keep your buttercream at the right consistency—not too stiff, not too runny—for easy piping

Common Mistakes

• Skipping the crumb coat can lead to a messy final look
• Piping too much frosting at once can cause colors to blend instead of looking like scales

Time-Saving Tips

• Bake the cake layers a day in advance and store them wrapped in plastic
• Use a turntable for smoother frosting application

Serving Suggestions

Pairings

• Serve with a side of vanilla ice cream or fresh berries
• Try pairing it with a light fruit punch for a fun party vibe

Presentation Ideas

• Top with edible pearls or a mermaid cake topper for extra flair
• Use a dusting of edible glitter to give the cake an ocean-like shimmer

Beverage Pairings

• A tropical smoothie or coconut-infused iced tea makes a great match
• Kids will love it with a colorful lemonade or sparkling fruit punch

Storage & Reheating

Leftover Storage

• Store in an airtight container at room temperature for up to 2 days or in the fridge for up to 5 days
• Freeze unfrosted cake layers for up to 2 months

Reheating Methods

• If refrigerated, let the cake sit at room temperature for 30 minutes before serving

Frequently Asked Questions

Substitutions & Adjustments

• Can I make this cake gluten-free? Yes, swap the flour with a 1:1 gluten-free blend
• Can I use a different color scheme? Absolutely! Try pastel shades or even bold neon colors for a unique twist

Troubleshooting

• My buttercream is too stiff. Add a little extra cream to soften it
• My colors are mixing too much. Chill the cake periodically during decorating to keep colors distinct

Variations & Customizations

Dietary Adaptations

• Make it dairy-free by using plant-based butter and milk alternatives
• Reduce the sugar by using a lower-sugar buttercream recipe

Flavor Twists

• Add a hint of coconut or lemon zest to the cake batter for a tropical vibe
• Try chocolate or strawberry cake layers instead of vanilla for a fun surprise inside

Seasonal/Holiday Versions

• For a winter wonderland version, use shades of blue and white
• Create a pastel version for Easter or a rainbow scale effect for Pride celebrations

Conclusion

This Purple and Blue Buttercream Mermaid Scales Cake is a showstopper that’s much easier to make than it looks. Whether you’re a beginner or an experienced baker, this cake will bring a splash of fun to any celebration. If you try this recipe, let me know how it turned out in the comments, and don’t forget to tag me in your photos on Pinterest at Cooking with Callie

Looking for more amazing cake ideas? Check out these recipes
Old-Fashioned Fruit Cake
Easy Barbie Cake
Old-Fashioned Southern Tea Cakes

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