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Fizzy Frosting Bath Cupcake Recipe

Fizzy Frosting Bath Cupcake Recipe

Make a fun bath treat topping that is activated by water

Use this recipe to make an exciting, versatile topping for your cupcakes, bath bombs, and other bath treats.

Question:  Why is this fizzy frosting/fondant different?
Answer:  It is activated by water!
Yes, it actually bubbles and fizzes when it touches water!

You can use this recipe to make two different toppings:  frosting and fondant.

To get frosting, you simply pipe it on a cupcake right after it is mixed. On this floating bath bomb cupcake, the pink was piped and the yellow lemon was made of fondant.

Floating bath bomb with fizzy frosting

Make toppers out of fondant

For fondant, let the frosting relax in an air tight container for about two hours and then roll it out like sugar cookie dough to make toppers (see below).

Make bath bomb cupcakes & toppers first

Make your toppers and bath bomb cupcakes on one day and then frost them on the second day.

Use Mini Cookie Cutters for Fondant

Cut the fondant into adorable shapes with Mini Cookie Cutters .  has almost 250 different shapes to choose from!  You can find something for any holiday or occasion.

Roll it out, texture, and then cut with a mini cookie cutter.

Pumpkin Bath Bomb Cupcake

Embed frosting chunks for spinning bath bombs

Later, you can embed chunks of left-over frosting in bath bombs for attractive designs.  The frosting will give your bath bombs light bubbles and slight buoyancy.  You can use it to make a floating bath bomb spin.

Starry Night Butter Bath Bomb. Fizzy frosting adds buoyancy and light bubbling.

Starry Night Bath Bomb

The following bath bombs were decorated or enhanced with this fizzy frosting recipe.

Pumpkin bath bomb cupcake. The mini pumpkins were rolled out of fondant and the white frosting was piped.

Pumpkin Bath Bomb

Santa’s floating bath bomb cupcake.  The green tree was made from fondant that was textured with a rolling pin and dusted with shimmer.

Santa Bath bomb cupcake

Embed colorful fondant hearts in this bath bomb recipe.

Bath Bomb with Fondant Embed

Fizzy Frosting is Awesome

So cool, right?   I was the owner of FizzButter Bath Bakery and I invented this fizzy frosting recipe.  I wanted a frosting that was activated by water.

It took some trial and error but this frosting recipe takes any bath treat recipe to the next level.

For Best Results:  Measure  Ingredients by Weight

This recipe is more technical than most so be as precise as you can with your measurements.  The best way to do this is by using a kitchen scale and convert this recipe to weight.

I use this exact Kitchen Scale  from Amazon for measuring ounces and grams.

Kitchen Scale

Get my favorite Kitchen scale from Amazon

Be a bath bomb wizard!

It’s very easy to measure by weight so do not be intimidated.  It will also help you to really get to know these ingredients and become a real bath treat wizard.

The first time you make this recipe, record the weight of each ingredient and then use weight measurements instead of cups and tablespoons on subsequent batches.

Fizzy Frosting Recipe / Bubble Fondant Recipe

Recipe authorFizzButter
Frosting Yield:  Frost around 15 large Wilton hearts.
Fondant Yield: 40 to 50 small toppers.


Buy at Amazon
IMPORTANT:  make your fondant toppers the day before you plan to frost cupcakes.

  1. STEP 1: Before you begin.

    You will need a hand mixer, Wilton 12-inch bags and one or two Wilton 1M star tips.  Never add fragrance to this recipe or your frosting will not rise correctly.

  1. STEP 2: Put the following ingredients in a bowl in this order:

Mix ingredients in a medium sized mixing bowl.  If ingredients stick to the bowl, scrape off and re-mix.  Mix just enough to get everything evenly distributed and move on.

  1. STEP 3: Add two more ingredients & mix

  • Mix in baking soda and cream of tartar. Note: this is regular kitchen cream of tartar and not tartaric acid.

  1. STEP 4: Add final two ingredients

  • 3 TBSP Corn starch
  • 4 TBSP citric acid (fine grain works best…like Milliard)

Once you add the citric acid to this mix, it is activated and must be worked with immediately!

Now, use this mixture to either frost cupcakes or make bubble fondant for toppers.

Let’s make fizzy frosting:

Fill your Wilton bag halfway, twist to hold, and pipe it on your cupcake.   On a heart, I liked to do a half circle swirl on each side and then do fill the middle.  It will depend on the shape of your bath cupcake.

Just remember, the frosting will rise about 60% so don’t put too much on the cupcake.  When that happens, it will slide too far off the sides and look less attractive.

After you pipe all your cupcakes, place your favorite topper on each cupcake while it is still wet.  We used fondant Christmas Tree’s, Pumpkins, Hearts and lemons.  This company has almost 250 different kinds of Mini Cookie Cutters so you can do something for every holiday or theme.

Do you have Leftover frosting?

Just pipe it directly onto wax paper, let it dry, break it into chunks and you can use it to embed in bath bombs.  It will add color, bubbles, and buoyancy to any bath bomb.  Once it dries you can store it for over a year in a ziplock bag.

For bubble fondant toppers:

Roll your frosting into a ball and place it in a tupperware container.  You have to use a pretty big container because the frosting will rise so much it may lift off the lid.

Let the fondant rest for about two hours.  You can tell it’s done when it stops rising like crazy.  Please note:  it’s better to use the fondant too early vs. too late.  Once it dries out, it is a useless substance and you will have to throw it away.

Test your fondant

Take a walnut sized piece to test.  Roll it out to 1/4 inch and finish with a texture roller.  Does it hold the texture?

When the fondant is just right, it acts and feels just like sugar cookie dough or fondant.  It holds impressions and you can use a cookie cutter to cut out shape.

Make Toppers from Fondant

Lightly ‘flour’ your work surface with baking soda.  Take an orange sized piece of fondant mixture and roll it out to 1/4 inch with your plain rolling pin.

Next, use a textured rolling pin and add creative texture to your topper.   Have fun

Finally, cut out your shapes with mini cookie cutters.

Fizzy Fondant Hearts

Make adorable toppers out of this bubble fondant.  Use different rolling pins to get different textures.

Topper Making Tips

Try to cut the toppers as close as possible.   In addition, I like to have around six mini cutters because they start to stick after a about 10 uses.  When you are starting out, use a less intricate design with fewer corners.

After you cut out your first set of toppers, add a little bit of new fondant to the unused fondant that was left around your cuts and roll it out again.  You can usually do this a few times but if the old mix starts to get brittle, just throw it out and use only new fondant.

Troubleshooting Fondant

If your batch is too wet, it will severely stick to the mini cookie cutter and it won’t hold a rolling pin texture (it will rise out of shape).

If this happens, simply add about a 1/2 tablespoon of baking soda and work it through your apple sized ball.

Now re-roll it out, add texture, and then cut toppers.

I like to use a flat knife to move the cut-out pieces to dry on wax paper.

The extra fondant mixture will dry out quickly so be sure to re-wrap it between use.

Air dry these in a low humidity area and store in sealed ziplock bags.  These will last for over a year if they are kept dry.

Rolling Pin Tips and Tricks

First, you’ll want to use a smooth rolling pin like this 9-inch Wilton fondant rolling pin from Amazon.  Wilton makes a longer rolling pin but this size works well with the small sections of fondant we will roll out at once (so it doesn’t dry out).

wilton rolling pin

Smooth Wilton 9-inch Rolling Pin from Amazon

Next,  use the smooth pin to get a 1/4 inch thickness on your bubble fondant.  It is nice to have more than one 9-inch pin on hand if you are planning to work with multiple colors or do a large job.  Please note:  Never use this mixture with an aluminum rolling pin.

Now, we get to have some serious fun!

There are a wide assortment of textured rolling pins to jazz up your toppers.

We used the purple textured rolling pin in the image below on our Santa’s Cupcake above.

Plastic textured rolling pins from Amazon.Rolling Pin Assortment.

Never put these plastic rolling pins in the dishwasher.  They have seams along the sides that allow water to get inside of them.

Overall, small textures work best.

We really liked this Wilton Fabric roller from Amazon because it catches shimmers exceptionally well.

Note:  Buy two of these if you plan to make a lot of toppers because it will start to stick and it’s very hard to wash and get all the way dry in the middle of a project.

Wilton Fabric Textured Rolling Pin

Wilton Fabric Textured Rolling Pin

Troubleshooting your Fizzy Frosting

Have I added too much water?

If your frosting rises over 100% and flattens out about 5 minutes after it is piped, you have added too much water.   This is when you will be happy you weighed all the ingredients because it makes it very simple to adjust.   Re-do your batch and you will usually want to take out a gram or two of water at a time.  

Also, you don’t have to throw away your work.  RECOVER EVERYTHING!  You can use this failed mix to make toppers.

Remove the frosting from the cupcakes as soon as you see it has flattened.  Next, roll the fizzy frosting into a ball, and then store it in inside a sealed tupperware container.  Once it settles and dries a little bit, you can roll it out like fondant.  This usually takes and hour and half to two hours.  

Have I used enough water?

If the mix doesn’t rise very much and is impossible to pipe through the bag, it does not have enough water.  It is not too late to fix this.  Put the mix back in the bowl, add a gram of water and mix.  Try to re-pipe.
Is storage important?
YES!!!!!   Humidity will cause this mixture to mold.  All toppers and cupcakes must be cured and stored in low-humidity (under 30%).
The good news is that your little toppers have a shelf life of over one year if they are stored in a sealed ziplock bag.
Cupcakes should be used immediately after opening.

Submit your review

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Fizzy Frosting
Average rating:  
 3 reviews
 by Delia

We made cupcakes and used this frosting. I like how it helps them float and the bubbles and color are cool. TY

 by Jerisha

It's prob the coolest thing ever. Wow.

 by Serena

Thank you so much for sharing. It worked great and I did little hearts textured with stars! Then, we dusted them with silver shimmer. They are amazing.


Wednesday 27th of January 2021

Did I miss something? How are you getting the frosting to stick to the bath bomb? I'm worried that once the cupcake has dried overnight, that the frosting won't adhere to the bottom-just sit on top & possibly fall off once it dries.


Sunday 26th of September 2021

To be extra sure, you can use a paint brush and put some water in the center of the cupcake before you frost it.

Wendy Gold

Thursday 16th of May 2019

Iv been doing a LOT of research (my head is just mush lol) about bathbombs/bubble bars and one question pops up all the time 'How do you stop the bath bomb from staining your bathtub'. How do you deal with this with your items?

Monica Schultz

Friday 4th of October 2019

use polysorbate 80


Thursday 16th of May 2019

Use a little bit of SLSA in your mix and don't go crazy with the colors.

Claire Fuller

Tuesday 5th of March 2019

Hi there! I am trying to make a smaller test batch of the frosting and the fondant for about 6 cupcakes as the meringue powder is extremely expensive where I live so I don't want to mess it up 😭 could u reccomend measurements for a smaller batch??

I'm so looking forward to making these!


Tuesday 5th of March 2019

What you can do is go to Michael's with a 50% off coupon. That's probably the cheapest way to get it. To do a smaller batch, you will have to divide the ingredients. Do a half batch. IT won't work right without the powder, though.


Thursday 14th of February 2019

Thank you so much for the fizzy frosting recipe! Can’t wait to play! Did you shrink wrap the cupcakes after they dried? How long until they are ready to package? Also, you mentioned with too much humidity, mild can grow. How did you store them until selling?


Friday 22nd of February 2019

Do not shrink wrap the cupcakes because they can break when you unpackage them. We just put them in tied off shrink bag for shipping. If we were selling these on the retail shelf, I would do a cute little windowed box, or something. It would protect it better.

Let them cure/dry for 2-3 days and then store them in individually sealed bags. You can tell if you put them in bags too soon (not dry) because after about 12 hours in the bag, the frosting starts to get soft and impressionable vs. hard like when you bagged it. If this happens, take it back out of the bag and let it cure for another day. It will not hurt it. Let me know if you have any other questions.