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.

View from above, the cupcake cake partly painted with gold edible paint.

A paintbrush painting piped buttercream mermaid scales with gold edible paint.

If you want to make another fun, mermaid-inspired dessert, try these glamorous meringue cookie pops.

Mermaid Tail Cupcake Cake

HOW TO MAKE A MERMAID TAIL CUPCAKE CAKE