Mermaid Tail Cupcake Cake

Say yes to a cupcake pull-apart cake decorated with creamy and smooth buttercream pastel hues and shimmering gold mermaid scales. This watercolor buttercream mermaid tail cupcake cake can light up a birthday party, baby shower or a bridal shower with a touch of magic and underwater fantasy.

Cake frosted with buttercream and painted with gold edible paint.

HOW TO MAKE A MERMAID TAIL CUPCAKE CAKE

Follow my step-by-step mermaid cake DIY tutorial.

THINGS YOU NEED TO MAKE MERMAID PULL APART CUPCAKE CAKE

24 Baked cupcakes – I used mini cupcakes, you can also use regular-size cupcakes. You’ll need a bigger cake board if using regular-size cupcakes. Try my Chocolate Cupcake Recipe.
1 batch Buttercream – I used this recipe for American Buttercream. You can freeze leftover for later.
Mini muffing pan or regular-size muffin pan
Mini cupcake liners
Gel Food Colors: teal/aqua, electric pink, regal purple (if you don’t have purple, you can use sky blue and electric pink to make purple), gold or ivory
Cake Decorating piping bags
Round piping tips: round tip #12, round tip #5, round tip #4
Spatula or flexible smoothers – to spread buttercream
Paper towel – Viva or use the side without texture to smooth the buttercream
Paint palette
Gold luster dust or edible gold paint (for example: Glamourous Gold by Sweet Sticks)
Paintbrush
19×13 inch large cake board or a heavy duty cardboard wrapped in foil or grease-proof paper

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BAKE CUPCAKES

Bake cupcakes and let them cool. You need 24 cupcakes to make a pull apart mermaid tail cake.

PREPARE AND COLOR BUTTERCREAM

I used American Buttercream to frost the cake. The recipe comes together quickly and is stable to leave at room temperature for a few days.

Color about 1/4 cup of buttercream with pink, purple and teal.
Color 1/3 cup of buttercream with ivory or gold gel color.
Leave rest white.

Three bowls with colored buttercream, pink, purple and teal.

MERMAID TAIL CUPCAKE CAKE TEMPLATE

Attach cupcakes onto a cake board, pipe a dot of buttercream on the bottom of each cupcake, and glue them onto the cake board. Don’t leave gaps between cupcakes.

Mini cupcakes arranged on a silver cake board.

You don’t need to print a template or anything like that. Just follow the cupcake arrangement you see in the image below.

Undecorated mini cupcakes on a silver cake board.

FROST THE MERMAID PULL APART CUPCAKE CAKE

Pipe buttercream onto the cupcakes and spread it over the cupcakes with a spatula and/or a flexible plastic spreader (steps 1-5). Let the cake sit for several minutes until the buttercream starts to crust. About Once the buttercream is lightly crusted, about 10-15 minutes, smooth the top with a paper towel. If you have a super soft and smooth Viva -paper towel, great, use that. But regular paper towel works, too. Turn the sheet over and use the nontextured side. Don’t drag the paper towel over the buttercream surface; gently dab it to smooth the buttercream (steps 6-8).

Spreading white buttercream onto a cupcake pull-apart cake.

EASY WATERCOLOR BUTTERCREAM

Use pink, purple, and teal-colored buttercream to create a watercolor design. Lightly spread pink, purple, and teal buttercream over white buttercream. Wipe the spatula in between (steps 1-6).

Spatula spreads pink, purple, and teal buttercream onto white buttercream frosted cake.

PAPER TOWEL METHOD FOR SMOOTH BUTTERCREAM

Allow buttercream to crust for 10-15 minutes and then use a nontextured side of the paper towel to smooth the top of the buttercream. Use a gentle dabbing motion.

Paper towel smoothing buttercream on top of the cake.

MERMAID SCALES PATTERN

Use a toothpick to draw the mermaid scale pattern onto a buttercream (steps 1-3).

Hand holding a toothpick, drawing the mermaid scale outline guide into the buttercream.

Cake frosted with watercolor buttercream with a mermaid scale guide indentations in the buttercream.

PIPE MERMAID SCALES – GOLD BUTTERCREAM

Fit a piping bag with a coupler and attach a piping tip #5. Pipe the border (steps 1-3).

Cupcake cake frosted with buttercream on a silver cake board.

I switched out a round piping tip #5 for #4 to pipe the scales. Follow the guide you made with a toothpick to pipe the mermaid’s body and the fluke. Chill the cake until the buttercream is firm, about an hour.

Piping bag piping mermaid scales onto a cake.

PAINT WITH GOLD EDIBLE PAINT

Shimmering details and mermaids go hand in hand, so you can’t blame me for adding an extra step, I just couldn’t skip on glittering gold. You can use edible gold paint or make your own with gold luster dust. Into a paint palette pour gold luster dust powder, and then pour in alcohol with a dropper ( I used Everclear). Mix it well with a food-only paintbrush (steps 1-4).

A small white paint palette with gold luster dust.

Carefully paint firm ivory/gold buttercream outlines with an edible gold luster dust paint. Don’t put too much pressure onto a paintbrush, as it can make dents in the buttercream. If the buttercream gets too soft to paint, chill it until firm, and then continue.