Foaming Cupcake Bath Bomb Frosting Recipe – Only 3 Ingredients

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diy cupcake bath bomb recipe with frosting

I would like to share with you a very easy DIY cupcake bath bomb recipe. Making DIY cupcake bath bombs is all about the frosting, and I have finally discovered a bath bomb cupcake frosting recipe that not only looks beautiful but is practical too.

DIY cupcake bath bombs are adorable and I have tried to make a few myself before but was never fully happy with them. I am not a fan of meringue bath bomb frosting as it’s sugar-based and does not perform well in water. I’ve tried butter-based DIY bath bomb frosting but I found it too greasy, too expensive to make, and too soft. There is also soap frosting, which looks great, but I don’t like that you have to remove it from the bath bomb before placing it into the bathtub.

What to expect from this cupcake bath bomb frosting recipe?

After a few experiments I have found a bath bomb cupcake frosting recipe that lives up to my expectations:

1. It is easy to make and requires only 3 ingredients

2. It is inexpensive (unlike butter-based bath bomb frosting)

3. It foams, which makes it fun to use

4. It is rock hard after it dries. This is very important because most of us want to be able to package our bath bombs for gifts or for sale.

These cupcake bath bombs look cute and can be decorated with sugar sprinkles or little soap embeds.

I love that you can just place the entire bath bomb into the water and it will perform beautifully. The “cake” part of the bath bomb fizzes and foams, while the frosting part creates beautiful soft foam. The finished cupcake bath bombs are very hard, so you don’t have to worry about breaking them.

Pin for later:

cupcake bath bomb frosting recipe

Things you'll need to make cupcake bath bombs

You will need the usual bath bomb ingredients to make cupcake bottoms:

- 1 cup of baking soda

- 1/2 cup of citric acid

- 3 tbsp of cornstarch. Cornstarch makes bath bombs harder and it also makes bath water feel very soft.

- 3 tbsp of buttermilk powder - adds foam

- 1 tbsp of light oil (cocoa butter is a great substitute)

- 1/2 tbsp of Polysorbate 80 - prevents dyes and mica from staining your bathtub and mixes oils with water. You can read about it here.

- Purple color dye (soap colorant, water-soluble dyes or food dye)

- 10 drops of Bubblegum fragrance or your favorite essential oils

To make bath bomb frosting you will need:

- 1 cup baking soda

- 1/5 cup of Cocamidopropyl Betaine. It is a very mild surfactant that is often used as a cleansing agent in gentle formulations. It also creates foam.

- 2 tbsp of white kaolin clay

- Pink mica powder or dye. I used mica powder for shimmer.

- A piping bag

You can make bath bomb frosting just with baking soda and C. Betaine but I personally achieved better results with added clay because it hardens the frosting. Clay can be substituted with cream of tartar.

cupcake bath bombs diy

How to make cupcake bath bombs

First, let’s make the cupcake bottoms.

1. Mix baking soda, cornstarch and buttermilk powder in a large bowl.

2. Add color. Start by adding a couple of drops and mixing. Add more until you reach the desired shade. You may need to spray a little bit of water to help the color mix better.

3. In a separate bowl, combine oil, Polysorbate 80 and fragrance/essential oils. Once combined, add it to the main bowl and mix.

4. Add citric acid.

5. Check the mixture by squeezing it in your palm. If the mixture stays together – it’s ready. If it crumbles, spray some water, mix and check again.

Now let’s make some cupcake bath bomb frosting:

6. Combine baking soda, C. Betaine and clay in a bowl. Add color of your choice and mix well.

making cupcake bath bomb frosting from a 3 ingredient recipe

7. Fill in a piping bag with the frosting mixture and you are ready to pipe.

pink cupcake bath bomb frosting recipe

If you have never used a piping bag before, here is a video showing some good piping techniques. And don’t worry if it didn’t work out for the first time. You can always remove the frosting and try again. Or, you can wait till it dries out and pipe a second layer on top to create bigger cupcakes.

Let your finished DIY cupcake bath bombs dry for 12 hours.

I hope you enjoyed the recipe and made some beautiful cupcake bath bombs in the process!

41 thoughts on “Foaming Cupcake Bath Bomb Frosting Recipe – Only 3 Ingredients

  • March 7, 2019 at 4:51 pm
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    Yay!! This is just what I was looking for… I think! Will definitely be trying soon 😁

    Reply
    • August 4, 2020 at 6:37 pm
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      may I use slsa to replace butter milk powder?

      Reply
      • November 23, 2020 at 1:45 pm
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        yes you can for bubbles or can use dry milk powder too for foam

        Reply
    • June 19, 2021 at 1:16 pm
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      Can you tell me how many grams or ounces 1/5 cup of coco B is

      Reply
      • November 21, 2021 at 1:32 pm
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        1/5 of coco B is 3tblsp.

        Reply
  • May 17, 2019 at 2:24 am
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    Hi, can i change clay to corn starch to make the frosting hard?

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    • May 19, 2019 at 7:48 am
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      Hi! Yes, cornstarch is a good substitute. Clay is, of course, stronger but cornstarch will do a great job too.

      Reply
      • November 23, 2020 at 1:46 pm
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        cream of tartar makes it hard too if you run out of clay

        Reply
      • January 11, 2021 at 5:19 pm
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        How many does this recipe make

        Reply
    • July 12, 2019 at 2:48 am
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      Hi, I tried the bath bomb frosting recipe but after careful measuring the ingredients, the mixture is far to dry for piping. Is there something missing from the recipe?
      Thanks Lesley

      Reply
      • July 13, 2019 at 7:50 am
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        Hi Lesley! It’s difficult to say why your mix came out too dry. These quantities work like a charm for me every time. The good thing is that it is very easy to adjust the frosting recipe. If your bath bomb frosting is too dry just add a bit more of c. betaine until you are happy with the consistency. If you start piping and it’s too wet, put frosting back to the bowl and add more baking soda to make it drier.

        Reply
      • June 17, 2020 at 7:34 pm
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        Does it get hard? If so, how long does it take to harden

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        • November 23, 2020 at 1:48 pm
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          yes it gets hard especially if you use clay or cream of tartar..it is hard in 24 hours but I always wait one more day before packaging though they will continue to harden after you shrink wrap them too

          Reply
      • February 23, 2021 at 11:10 pm
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        You could also try and little bits of rubbing alcohol.. It will also Harden the icing

        Reply
    • September 21, 2019 at 11:45 pm
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      Thank you for this! 💖💖

      Reply
    • October 23, 2019 at 4:26 pm
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      Why is the frosting refusing to come through the tip? Is it just me or does everyone have this problem?

      Reply
    • May 4, 2020 at 11:29 pm
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      Hi,
      Would love to try to make this cupcakes but have such a hard time to find the C betaine. The link you shared from amazon it is unavailable an they don’t know when they will have it again. Is there anything else that can be used instead?

      Reply
      • June 11, 2020 at 8:56 pm
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        Go to https://www.wholesalesuppliesplus.com/search.aspx?q=Bubbleup
        Buy Crafters Choice bubble up. It’s the same exact product for $3.50 a lb. If they are sold out just google the products full name & you’ll see lots of candle making sites sell soap supplies as well. You can always find it at one of these sites for really cheap!

        Reply
      • November 23, 2020 at 2:03 pm
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        the comment below is awesome very cheap and you can get it from many suppliers but I really love wholesalesupplies.com they sell everything and cheap! every week items are on sale weekend sales etc.. the coco B is cheap there and if your order is 40 or over free shipping! they also have many many recipes for all kinds of products too 2000 recipes!

        Reply
  • August 23, 2019 at 4:52 pm
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    How important is the cocamidopropyl betaine? Is it possible to substitute soap?

    Reply
    • June 11, 2020 at 3:56 am
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      Hi I have made this frosting still not complete hard after three days

      Reply
  • August 23, 2019 at 4:52 pm
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    How important is the cocamidopropyl betaine? Is it possible to substitute soap?

    Reply
    • November 23, 2020 at 2:05 pm
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      no you have to have it..the main ingredient.. it is what makes it all bubble up and hold together its the surfactant..not spelled right sorry

      Reply
  • September 23, 2019 at 2:22 pm
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    Great recipe! Loved it and no powder sugar!!!

    Reply
  • October 12, 2019 at 6:28 am
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    Can you make the bath bombs and later put on the cupcake topping.

    Reply
  • December 13, 2019 at 7:51 am
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    Pardon me for missing something…Why no citric acid in the frosting? Does it get enough from the rest of the bomb?
    Or would the CocoBet activate the reaction?
    I’m going to try it both ways anyway, lol…we shall see…

    Reply
  • February 18, 2020 at 10:52 am
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    I made them both ways as when I used the C Betaine my frosting was just way to foamy to pile.
    Although it still dried fabulously it just looked horrible so I would say make it however you can work with the frosting as they all fizz anyway ❣️

    Reply
  • May 3, 2020 at 5:29 am
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    I have tried this recipe twice and has not worked. Quite frustrating when you spend lots of money on ingredients.

    Reply
    • June 11, 2020 at 9:02 pm
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      I’d try more Kaolin Clay as that is the hardener in the frosting.

      Reply
      • March 3, 2021 at 8:53 am
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        Mine started crumbling when hardening process started. I packaged mine before the frosting could completely set as I am in quite a humid climate. Could this be the issue?

        Reply
  • May 13, 2020 at 1:57 pm
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    Made the frosting today, looks amazing. Not sure how hard it really gets so let see in a couple of days.

    Reply
  • June 11, 2020 at 3:46 am
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    Hi I have made this frosting still not complete hard after three days

    Reply
  • October 10, 2020 at 10:24 am
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    This bath bomb frosting is wonderful! Thank you so much! It is so easy to make,it hardens up good and gives a ton of bubbles! It is so easy to make I don’t even need to measure much just add more baking soda and clay for a bigger batch then add enough of the Cocamidopropyl Betaine(or Bubble P)To pipe.It hardens pretty fast to.

    Reply
  • October 18, 2020 at 4:34 am
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    How many does the recipe make?

    Reply
  • November 27, 2020 at 11:52 am
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    esquil ya des risque de moisisure entre la bombe de bain et le glacage

    Reply
  • December 7, 2020 at 9:35 am
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    Do these float or sink?

    Reply
  • January 6, 2021 at 5:45 pm
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    Very new to making bath bombs so please excuse me if this is a “duh” question-lol
    I love your recipe for bath bombs but I am curious as to why the bottom of this cupcake has much less in it – isn’t it just a bath bomb in the bottom of the cupcake?(the bath bomb recipe I’m referring to is the one where you explain why poly80 is a game changer)

    Reply
  • February 17, 2021 at 8:43 pm
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    Hi there from the UK. Your recipe is fantastic. The only problem I have is that the frosting separates from the base after it dries. Is there anyway to get it to stick. Thank you x

    Reply
  • April 23, 2021 at 9:32 pm
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    Hello!
    I have question
    How long should be waiting to put decolation on the frosting?

    Reply
  • May 21, 2021 at 1:47 pm
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    To get the frosting to stick you must have a hole or something in the bath bomb for the frosting to “hold” onto. I pipe the hole first then let it sit awhile then I go back and pipe the remaining top of the frosting.

    Reply

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