These rubber duck cupcake melt and pour soaps have a yellow cake base and a whipped aqua soap frosting shaped like rough ocean waves, with a little rubber duck floating on top. I made them as a test run for party favors. Instead of piping the frosting, I whipped the soap and roughed it up to look like water.
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Materials & Tools
Soap Base
- Goat’s milk melt and pour soap base for the cake and the frosting
Color & Scent
- A yellow colorant for the cake and an aqua for the frosting (I used Bramble Berry’s concentrated Canary and Aqua lab colors). Mica from a Stardust mica set works too.
- Birthday Cake fragrance oil. It contains vanilla, so it can turn the soap a little brown over time.
Tools
- Silicone cupcake cups set in a muffin pan
- Hand mixer with whisk
- Small rubber ducks for decoration (I found mine at Oriental Trading)
- Small plastic spoons and skewers
- Spray bottle of 91% isopropyl alcohol
- Thermometer
Fragrance Amount
Use up to 5 ml of fragrance oil per 16 oz (1 lb) of soap base. You can always use less if you like a lighter scent, but don’t go over 5 ml per 16 oz.
How to Make Rubber Duck Cupcake Soaps
1. Color the Cake Base
Melt the goat’s milk base and add your fragrance. A vanilla fragrance can turn soap brown, so add a little yellow. The yellow helps offset the browning, and a little brown just looks more like cake anyway.
2. Pour the Cupcake Bases
Set the silicone cupcake cups in a muffin pan so they hold their shape. Pour the cake soap (mine was about 150°F) and let it set.
3. Make the Aqua Frosting
Melt more base, add fragrance and color it a fairly dark aqua, so any browning from the vanilla won’t show.
4. Whip the Soap
Whip the soap with a hand mixer, starting on the lowest setting. As it cools to around 118–120°F, it reaches trace and fluffs up a lot. My quarter cup grew to almost two cups.
5. Score the Cupcakes
Score the tops of the set cupcakes with a skewer and spray them with alcohol so the frosting sticks.
6. Spoon on Rough Waves
Spoon the whipped soap on and dab at it so it looks rough and airy, like choppy water. Press a duck into the frosting. If the whipped soap sets up too fast, remelt it in very short bursts. Ten seconds really means ten seconds, because airy soap melts fast.
7. Try Soap Shavings for Texture
For a second version, let some whipped soap harden, then scoop it with a spoon into curly shavings. Spray the duck with alcohol, spoon a little warm soap around it as glue, and press the shavings all around the duck in sections.
8. Unmold
Let the cupcakes set, then peel off the silicone cups. Whipped soap stays a little soft and rubbery, and that’s normal.
Tips & What I Learned
- Do a test run. It’s the best way to work out a design before making a big batch.
- Offset vanilla browning. A little yellow in the base helps.
- Whip to about 118–120°F. That’s when it fluffs up.
- Remelt whipped soap carefully. Use very short bursts.
- Keep the decorations light. A full rubber duck soap would be too heavy for the frosting.
Troubleshooting
The frosting set up before I finished.
Remelt it for a few seconds and whip again.
The frosting slid off.
Score the top and spray with alcohol first.
The soap turned brown.
Vanilla in the fragrance causes that. Add a little yellow or a darker color.
FAQ
How much fragrance oil should I use?
Up to 5 ml per 16 oz of soap base. You can always use less, but don’t use more than 5 ml per 16 oz.
Are the rubber ducks soap?
No. They’re small toys used as decorations, and they come off once the soap gets wet.
Can I pipe the frosting instead?
Yes. Melt Whip & Pipe would give a piped look. See my Melt Whip and Pipe soap frosting post.
More Cupcake Soap Ideas
- Cupcake Swirl Melt and Pour Soap
- Unicorn Cupcake Melt and Pour Soap
- How to Make Whipped Soap
- Cupcake Melt and Pour Soap 3 Ways
- All my melt and pour soap tutorials on YouTube
If you make this, I’d love to see it! Tag me on Instagram or Pinterest, and subscribe on YouTube for new soap tutorials.
