This cupcake swirl melt and pour soap has a white frosting with blue swirls running through it and a soft pink cake on the bottom. It’s made in a giant silicone cupcake mold, so there’s no piping involved. The trick is getting the soap cool and thick before you add the color, so the swirls hold their shape.
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Materials & Tools
Soap Base
- Detergent-free goat’s milk or shea butter melt and pour soap base, about 2 oz (¼ cup) for the frosting and 2–3 oz for the cake
Color & Scent
- A blue mica for the frosting swirl (I used Slushy Blue from Bramble Berry) and a bright pink for the cake (Electric Bubblegum), or colors from a Stardust mica set
- A little distilled water for the swirl, and alcohol for the cake color
- Fragrance oil
Tools
- Giant cupcake silicone mold
- Coil (flat) whisk
- Pipettes
- Thermometer
- Spray bottle of 91% isopropyl alcohol
- Shrink wrap bags (6 x 5, not 4 x 6)
Fragrance Amount
Use up to 5 ml of fragrance oil per 16 oz (1 lb) of soap base. For a 5–6 oz cupcake, that’s about 2 ml. You can always use less, but don’t go over 5 ml per 16 oz.
How to Make a Cupcake Swirl Melt and Pour Soap
1. Measure the Frosting Section
Fill just the frosting part of the mold with water and measure it, then mark the line on the mold. Mine holds about 2 oz, or ¼ cup.
2. Melt and Cool the Frosting Soap
Melt about 2 oz of base and add your fragrance. Let it cool as much as possible, down to the 110s or 120s°F. Without a thermometer, keep stirring with a skewer until it thickens. If a thin skin forms, just stir it back in.
3. Mix the Color with Distilled Water
Mix a small spoonful of blue mica with about half a dropper of distilled water. Mica mixed with alcohol would disperse and turn the whole frosting blue. Don’t use too much water, or the soap won’t harden properly.
4. Squirt, Twist and Pour
At about 118°F, stir the soap so it’s as thick as possible. Squirt about half a dropper of color in hard, push the coil whisk down, twist once and lift it up. Pour right away into the frosting section without any more stirring. A coil whisk reaches the bottom of the cup much better than a stiff whisk.
5. Let the Frosting Set
Leave the mold still so the swirl doesn’t move. After a minute or two, spray the bubbles with alcohol. Let the frosting harden with a thick skin before you pour the cake. This thick mold holds heat in the middle.
6. Pour the Cake
Melt another 2–3 oz of base and color it pink with mica mixed in alcohol. Here you want the color to disperse evenly. Let it cool to about 115°F. Squirt a little alcohol onto the frosting with a dropper and swirl it around so the layers stick, then pour the cake slowly to the top. Spray the bubbles with alcohol and let it cool for several hours.
7. Unmold
Peel the mold up all the way around the edges, then push down on the top to pop the cupcake out. Mine weighed about 5–6 oz.
8. Let It Harden and Wrap
Let the cupcake harden for a couple of days. Then shrink wrap it in a 6 x 5 bag. It’s easier to fit than a 4 x 6.
Tips & What I Learned
- Cool the frosting soap well. Around 118°F keeps the swirl from spreading.
- Use distilled water for the swirl, alcohol for the cake. Water keeps the swirl. Alcohol gives an even color.
- Go easy on the water. Too much keeps the soap from hardening.
- Use a coil whisk. It reaches the bottom of the cup.
- Glue the layers with alcohol. Squirt and swirl it on the frosting before the cake pour.
Troubleshooting
The frosting turned all blue.
The soap was too hot, or the mica was mixed with alcohol.
The cake sank into the frosting.
The frosting wasn’t set enough. Wait for a thick skin.
The two layers separated.
Spray alcohol on the frosting before pouring the cake.
FAQ
How much fragrance oil should I use?
Up to 5 ml per 16 oz of soap base, or about 2 ml for one cupcake. You can always use less, but don’t use more than 5 ml per 16 oz.
How much soap does the cupcake mold hold?
About 2 oz in the frosting and 5–6 oz total.
Can I use other colors?
Yes. Try any mica you like for the frosting swirl and the cake.
More Cupcake Soap Ideas
- Giant Cupcake Melt and Pour Soap
- Cupcake Melt and Pour Soap 3 Ways
- Unicorn Cupcake Melt and Pour Soap
- Flower Swirl Melt and Pour Soap
- 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.
