A DIY Kinder Surprise Bath Bombs Tutorial

Bath bombs are great, but bath bombs with presents inside are AWESOME. Here's how to make them using chemistry and magic!

I find relaxing very stressful. This is becoming a big problem in my life.

I’ve always dealt with stress through exhaustion, not relaxation. I work out until I can’t move, read until my eyes hurt, write until my wrists ache. And do you know what this has gotten me? A pulled muscle in my thigh, the beginnings of a stress ulcer and the ever-increasing urge to run out into the street and start knocking people’s hats off.

I can’t take to the sea, so something’s gotta give.

I’ve been trying to establish new, stress-fighting rituals so that I don’t end up a quivering mess of bile and rage by the time I’m thirty. While some things don’t work for me and my brain (I recite multiplication tables when I’m meant to be meditating, so that’s out), other things have been working really well.

Like taking hot baths. It turns out I really like sitting in darkened room, in a tub of very hot water, and staring at my feet for half an hour.

So naturally, I was like “How can I make baths EVEN BETTER?” And one of my friends was like “Bath bombs, duh.”

I enjoy endothermic chemical reactions as much as the next girl, so the idea of throwing something fizzy into my bath was already pretty fantastic. The thing is, most nice bath bombs cost like ten bucks a piece, which means I’d be spending approximately one million dollars on scented water every week.

Instead of going into debt, I started looking around for how to make my own. I tried a bunch of recipes that I found online and none of them worked properly, so I learned from my mistakes (and brushed up on my chemistry to understand why those mistakes were happening) and cobbled together my own super bath bomb formula.

All the ingredients together cost about seven dollars, which is good.

Then I made it even better.

Most bath bombs have stuff like flower petals and glitter in them, which is good...but what would be even better? Presents! So I stuck prizes inside.

Nothing expensive, obviously; just little trinkets that would show up after the bomb fizzes away. It’s like a Kinder Surprise for your bathtub!

I’ve been going nuts with this ever since I figured it out, because it combines two of my favorite things: chemistry and super tiny stuff. I’m making them for all my friends, because what says “I love you” better than a fizzy bath bomb with a present inside?

And now I’m going to teach you how to make them. Sharing the love!

Here’s what you’ll need:

  • 2 cups baking soda (bicabonate of soda)
  • 1 cup Epsom salt (Magnesium Sulfate, so relaxing!!)
  • 1 cup powdered citric acid (find in the canning section of the grocery store)

This 2:1:1 ratio works best, plus it's easiest to remember. Some recipes act like you NEED cornstarch to make the bombs fizz, but that's baloney. It has nothing to do with the production of carbon dioxide, and it annoyed my skin. Skip it.

You’ll also need:

  • Essential oils or fragrances (look in the soap-making section of the craft store)
  • Water-based dye (food coloring may stain certain tubs/skin/towels)
  • Oil of your choice (I used extra-virgin olive oil, but I know how you guys love coconut oil)
  • Mixing bowls (one big and one little)
  • A measuring cup and measuring spoons
  • Cooking spray or olive oil
  • Gloves (so you don’t stain your hands)
  • Spray bottle full of water
  • Wax paper (preferably on a baking sheet)


  • Toys/trinkets/prizes (raid the party store or the miniature section of the craft store)
  • A mold (make sure it’s deep enough to hide the toys)

Here's how you put it all together. We'll go ahead and call this the METHOD section, since we're using so much chemistry:

To avoid any premature chemical reactions, mix your dry ingredients together first in your big glass mixing bowl. This is the Epsom salt, bicarb and citric acid.

Most recipes say to mix your liquids into the bowl first, then add the dry ingredients. DO NOT DO THIS. This causes a giant fizzy calamity at the very bottom of your bowl, which you won’t notice until you try to stir it and realize it’s a globby mess.

Instead, in another mixing bowl (this one is ceramic), mix your olive oil and fragrance together. The oil is to make your skin soft, and the scent is just for fun--you can skip these things if you like.

I used four tablespoons of olive oil and a tablespoon of my fragrance, but you can use as much or as little as you want. I wanted my bath bombs to smell like summertime, so I bought one vial of coconut fragrance and one of pineapple-cilantro and mixed them together. Because who doesn’t want to smell like a piña colada?

Now you have to mix your wet ingredients with your dry without causing a bubbling calamity. This is the easiest, least dramatic way to do it that I’ve found, and it all revolves around GOING VERY SLOWLY.

Take one tablespoon of the olive oil-fragrance mixture and drizzle it in. Then add about a quarter teaspoon of your dye. I mixed a couple drops of yellow in with mostly blue to make this pretty sea green.

Take your spray bottle full of water and spritz the mixture a few times. It will fizz A LITTLE--the water is what causes the release of CO2--and that’s okay. Just so long as it doesn’t bubble like a cauldron. Then mix very well. Use a spoon or your hands if you want (but wear gloves if you do, the straight dye will stain your fingers).

Repeat this process until all your ingredients are combined and it’s the colour that you want.

If you need to separate your mixture into two bowls, that’s okay. It seems to expand like bread, and my mixing bowl was kind of small.

You’ll know the mixture is the right consistency when you can squish it in a ball in your hand and it holds its shape. If it crumbles on you, it’s too dry and you need to add more sprays of water. If it oozes out of its shape, it’s too wet and you need to add some more dry ingredients. Neither is a big deal.

Now we do the fun stuff.

Grab your mould and spray it with your cooking spray (or grease it with a couple drops of olive oil). Yep, even if its made of silicon. This will make it easy to remove the bath bombs.

Fill it about a quarter of the way with your mixture. REALLY pack it in there; think like you’re filling a bucket with damp sand to make a castle. Then take whatever you’re using as a prize--I’m using these awesome Captain Planet-style rings and mini rubber duckies, but you can use whatever you like--and stick them in.

Cover up your prizes with more mixture. Again, REALLY pack it down tightly. At first I was being super-delicate and using a spoon for this, but then I wised up and used my hands. Way easier. This dye doesn’t get on your skin after it’s been mixed in, by the way, but food coloring DID.

Make sure the back is nice and flat. I used the end of my spoon to draw a heart on mine for pretty much no reason.

Now flip your mold over onto your wax paper and squeeze super gently on the sides until the bath bomb pops out.

I also made some mini heart-shaped ones with only a duck OR a ring inside, because I didn’t have enough mixture left to make another big square one. What I'm saying is, this recipe makes A LOT of bath bombs!

You have to let these “set” for like 24 hours, which is why I suggested putting the wax paper on a cookie sheet--because then you can move them around. Stick them in a cool, dry place that’s out of direct sunlight and let them get hard. Hurr hurr, HARD.

In a day’s time, come back and check your handiwork. Congratulation, you’ve just made a Kinder Surprise bath bomb.

Once they’re set, Martha Stewart suggests storing them in glass jars with screw tops and writing the scents in coloured ink on vellum. Coordinated ribbon is also involved.

Which, okay. Do you, Martha. But my handwriting kind of sucks, I don’t have fancy glass jars lying around, and I’m not 100% sure what vellum is. So if I were keeping these for myself, I’d stick them in an airtight plastic container to make sure they stay fresh…

...And if I were giving them to friends, I’d put a couple in an airtight plastic bag, then slip that inside a little colorful gift bag. I’d try to make it look fancy with some tissue paper, but I’m just not on Martha’s level when it comes to packaging.

When you drop one of these suckers into the bath, it fizzes up really nicely while the water changes colour and your bathroom fills with a beautiful smell...

...And then once it’s all melted away, SURPRISE! A present!

I gave some of my first attempts to my friends, and they have reported that this was a delightful experience. Take their words for it!

Words can’t express how psyched I am about how well this turned out. It really makes all the experiments and epic screw-ups worth it. Now I can enjoy relaxing baths in lightly colored water, smell like a magical tropical island and have soft skin afterwards EVERY DAY OF THE WEEK.

I feel less stressed out already.

Do you guys like baths? I never really thought I was a “bath person” because I have problems sitting still, but I was SO WRONG! Are you going to try to make these? Do you love tiny stuff as much as I do? What miniature things would you hide inside bath bombs?