How To Prevent Royal Icing Craters (What Actually Matters)

Hey Bestie! I think it’s safe to say every cookier has encountered a royal icing crater at least once. And some cookiers are plagued with these little buggers regularly. It’s one of the unfortunate pitfalls (no pun intended) that unites cookiers. And over the years there continues to be theories, myths, hacks and tricks to try to prevent royal icing craters for good. Well, if you’ve been here before, you know I love some cookie research. So I decided to test them all myself. Read on to see all the variables I tested, what made a difference and what didn’t. Sink into your seat while we tackle craters…pun intended that time.

what causes royal icing craters?

Along with several different theories on how to prevent craters, there are several theories on what causes royal icing craters to begin with. Many believe piping on top of dried flood causes the flood to draw moisture from the wet icing on top of it, sucking the moisture into the flood causing the crater. And while my testing showed some evidence on this theory, it’s definitely not the sole reason craters occur.

The science also tells us that since icing dries from outward in, when the outer edges of a shape set, the inside doesn’t have enough structure to support itself, causing the area to crater in the center. Testing proves that how your icing dries may play the biggest role in preventing craters.

Lastly, the invisible, molecular structure of your icing matters. The way your icing is made creates your icing’s structure and protein network that prevents color bleed and other icing issues. If you’d like to learn more about making royal icing with a strong structure, THIS post will help.

So in our quest for preventing craters, we’re starting with an icing with good structure, and we’ll put the other variables to the test.

The royal icing crater experiment

We’re putting all the most popular hacks and theories to the test today to see exactly what works best and what’s a waste of time. In order to correctly study each variable independently, we’ve got 4 cookie test subjects. Each cookie includes 4 piped balloons on top of a flood base.

piping methods

• One balloon (mint green) will test the theory of whether piping squiggly lines of icing before filling/flooding the area makes a difference in cratering.
• One balloon (blue) will test the theory of whether poking holes in the flood base before flooding the area makes a difference in cratering.
• One balloon (violet) will be flooded with a 15-second flood consistency to test whether this consistency impacts cratering.
• One balloon (pink) will be piped with a thicker, puffy icing consistency to see whether this consistency makes a difference.

drying methods

In addition to the four different piping methods, we will be comparing the difference in results when cookies are airdried versus spending 20 minutes in a dehydrator.

Flood base timing

And on top of all those variables, we’re also comparing the results when the balloons are piped on top of crusted icing versus fully dried icing.

No stone will be left unturned, bestie, we’re testing it all! In summary, these 4 cookies are our test subjects. All 4 cookies will be decorated the same, with the same icing. But two will be piped when the icing is crusted while the other two have a fully dried flood base. And one of each of those will be air dried while the other spends 20 minutes in the dehydrator after the balloons are piped.

royal icing crater results

So what made the biggest difference after all the testing? Hands down, the cookies that spent 20 minutes in the dehydrator after being piped, had the best overall results. There was no difference in piping methods when cookies spent time in the dehydrator. There was no cratering at all in any of the balloons.

I will say, I could notice the tiniest hint of sinking in our balloons on the cookie where the balloons were piped on top of fully dried flood.

If air drying, the best results came from piping on top of crusted icing and using the thick, puffy icing consistency.

In all scenarios, there was no noticeable benefit or difference made by piping squiggly lines or poking holes in the base layer.

Long story short? Using a dehydrator is hands down the most effective way to prevent royal icing craters. No need for squiggles, poking holes, etc. Just let the dehydrator do the work for you. If using a dehydrator for decorating is new to you, THIS post will help cover all the things. Including the first question, “will it dry out the cookie?” Spoiler alert: Nope. Cookie texture is unaffected.

See the crater study video!

I covered a lot here, but I also made you this video explaining exactly how this crater study was conducted and you can see exactly how it was performed, along with all the results HERE.

Summary

I hope this royal icing crater study was helpful! It was fascinating to compare the results, bust the myths and finally figure out what makes a difference and what doesn’t. After all, we all just want the most beautiful cookies in the most efficient way. I’ve been using a dehydrator for every single cookie I decorate for years for all the benefits, so I can’t say I’m shocked at the results here. But it’s great to know that you can skip all the other tricks that aren’t providing any benefit.

Helping fellow home bakers is all I do every day, so let me know if this was helpful for you! And if you hear of other cookiers struggling, please share this so the circle of love can continue. If you need any more help, you can find me and thousands of fellow Besties HERE. It’s the happiest corner of the internet where you’ll find endless help, support, inspiration and celebration of beautiful bakes. And I’d LOVE to see your cookies there too!

And if you’re not already receiving my free weekly newsletter, you are missing out! Many Besties say it’s their favorite email of the week! You can subscribe below so you never miss out on a new recipe, technique, tutorial, product recommendation and all the free printables! Happy Baking, Bestie!