Soap Frosting Tips

chocolate soap cupcakes | bramble berry

If you love dessert as much as we do, you have to try soap frosting. It looks adorable on bakery-inspired recipes like soap cupcakes, and it can also be used to create shapes like leaves, flowers, etc. All it takes is a few tricks and some practice piping. We'll help you get started!

Cold process soap

There are a few ways you can make frosting with cold process soap. All you need is a stand or hand mixer, spoon, tall cup, piping tip, and a piping bag. You can even use a plastic bag with a small cut in the bottom corner. 

How to make it
You can make two separate batches. The base is a normal recipe, and the frosting is a mixture of mostly hard oils and butters. It's cooled, whipped with a stand mixer, and then piped on. It has an amazing consistency that allows you to create intricate details, but it does take a few extra hours of prep work. Learn more about this method in the Sparkling Champagne Soap Cupcakes video.

You can also use one recipe, which saves time. Just stick blend the soap to thin trace and split some off for the top. It will thicken as you make the base. If it's still too thin when you're ready to use it, you can let it sit another 5-10 minutes or speed it up with a few bursts from the stick blender.

The consistency you're looking for is similar to pudding. It needs to be thick enough to hold its shape, but not so thick that it starts to solidify. The best way to know is to test it. Place your piping tip in a piping bag or plastic bag, then put it into a tall cup and scoop some soap in. The cup makes this process faster and less messy. Pipe some frosting onto a piece of paper or spare mold. If it holds its shape, you're ready to go. This is also a great time to practice your design.

See how to use this method in the Orange Grove Soap video below.

As with any technique, soap frosting takes some practice. Here are a few things we learned along the way.

  • A recipe with a good amount of hard oils and butters sets up more quickly and hold its shape well. The same goes for a recipe with a water discount. Learn more in the Water Discounting Cold Process Soap article.
  • It's hard to know exactly how much soap you need to frost. You'll lose some as it's transferred to the bag, and you may find you want more height as you start piping. It's better to have enough for the entire design, so we recommend at least 10 ounces. Keep an extra mold nearby for any leftovers.
  • Once you hit thin trace, split the soap off to thicken. If it sits for too long it can get too hard to pipe.
  • Start with a simple design! A 1M frosting tip creates a pretty spiral design, and all you have to do is pipe it on. You can even skip the tip and pipe straight from the plastic bag.
  • Pipe onto a piece of paper first so you can check the consistency and get your design down.
  • If you want good height, pipe a row down the entire length of the soap. Then, pipe on top of that row. Building up is easier than trying to create one large dollop.
  • Made a mistake? No problem. Just gently scrape the frosting off, put it back in the piping bag, and try again.
  • If you make two batches, don't wait too long to pipe on the frosting. We've had the best results when it's piped within 24 hours. More than that and the frosting may separate.
  • We recommend avoiding gel phase. If the soap gets too hot, the piped top can lose its shape. You can keep the mold at room temperature or put it in the fridge or freezer for 24 hours. 

piping cold process soap frosting | bramble berry

Melt and pour soap

Like cold process, there are a few ways to create melt and pour frosting. You need the same equipment - a stand or hand mixer, spoon, tall cup, piping/plastic bag, and the piping tip of your choice.

How to make it
The first method uses Foaming Bath Butter. It creates thick, fluffy frosting that's easy to pipe. In a large bowl, add 1.5 cups of Foaming Bath Butter, 6 tablespoons of meringue powder, and 1.5 tablespoons of liquid glycerin. Whip with a hand or stand mixer until it's fluffy. Then, transfer to the bag and pipe onto melt and pour soap. We've had the best luck piping on soap that has dried and cooled for 30 minutes to 2 hours. If it's still warm, the frosting can warp or sink a little.

The second method is a mixture of melt and pour and liquid soap. It has a looser texture that won't hold a lot of shape. It looks a bit like foam, so we like using it for beer or coffee-inspired recipes. To make it, combine 5 tablespoons of liquid soap and 8 ounces of melt and pour soap. Use a hand or stand mixer to whip until frothy, then spritz the soap base with alcohol and pour the frosting on. Don't spritz again with alcohol, otherwise the top can deflate. See the process in this throwback video - How to Make Soap Cupcakes with Whipped Frosting.

whipping soap frosting | bramble berry

Unlike cold process, these frosting recipes never get really firm. They hold their shape, but they can also dent with pressure. We recommend letting them sit in a cool, dry place for a few days to fully harden. Then, enjoy or package them carefully.


  • Because the Foaming Bath Butter frosting has glycerin, it's prone to sweating. Make sure to wrap the bars tightly with plastic wrap and store them in a cool, dry place. If you live in a very humid climate you may want to invest in a dehumidifier to help with storage.
  • You can make the Foaming Bath Butter frosting without meringue powder. Just keep in mind it will be softer and won't hold any intricate shapes.
  • Feel free to scent the frosting. We recommend using the light recommendation on our Fragrance Calculator so there's not too much extra liquid. 
  • You can also color the frosting. Lab Colors or mica mixed with alcohol or glycerin work well - just add a few drops and whip to combine. Lab Colors are water-based dyes, so they may bleed onto the soap base.
  • If you want to gift or sell melt and pour soap frosting, try shipping it in a cupcake box surrounded by shock-absorbing material like paper or bubble wrap. That helps prevent denting.

raspberry truffle soap | bramble berry

More resources

Katie with Royalty Soaps creates amazing designs with soap frosting! Best of all, she shows you how to get the look on her YouTube channel.

These frosting videos by Luna Fae Creations and Ophelia's Soapery are helpful as well.