Sometimes I try to resist cake trends, other times I hop right on them. This sprinkle fault line cake design was way too awesome for me to resist!!

It’s almost reminiscent of the whole geode cake trend, but takes on a different geological concept…fault lines!

I first became aware of this trend when I saw a fault line cake made by @cakedesignbysheri. She’s an amazing cake decorating, and definitely inspired me to try my hand at it!

Below are a few tips I learned along the way that will help you make the perfect fault line cake.

Converging Fault Lines: Make Your Fault Outline Larger Than You Want It To Be

I took an elective class on volcanoes in college (it was surprisingly harder than you’d think), and we learned all about convergent and divergent fault lines.

As I was decorating this cake, I realized that all fault line cakes are convergent fault lines. As you smooth the frosting, you have to apply pressure with your offset spatula and bench scraper.

This causes the frosting fault line to get pushed closer together. It also means that your fault line will end up being smaller once your cake is smoothed.

Keep this in mind when you pipe the outline of your fault line. It should be bigger than where you want it to end up.

What Types Of Sprinkles Should I Use?

While you might think all sprinkles are created equal, sadly they’re not. When making this funfetti cake recipe, you have to be sure you use the right type of rainbow sprinkle.

The best sprinkles for making a funfetti cake are rainbow jimmies. They are the longer sprinkles, that you used to (and may still) put on your ice cream. These sprinkles keep their color, and won’t bleed into your batter.

This is important, because it will help your batter say white while you add it to your pans. This will allow the color of the sprinkles to really shine through once the layers are baked.

If you really want to be picky about your sprinkles, I also recommend getting a rainbow sprinkle blend that doesn’t have any chocolate/brown sprinkles in it. Funfetti cake layers look so much better without any brown sprinkles!

The type of sprinkle you should NOT use in your cake batter are the tiny, round, rainbow sprinkles. They’re called nonpareils, and they are the true enemy of funfetti cake layers.

Nonpareils will start to bleed their colors the second they’re stirred into your cake batter.

It will turn the batter a gross, pink/grayish batter. This can also happen if you let you rainbow jimmies sit in your batter for an extended period of time, and then try to stir it.

I used the same sprinkles to make my funfetti cake batter, fill the center of my cake, and fill my fault line.

However, you could use a fun sprinkle blend to decorate your fault line. My one word of caution is that if there are any large sprinkles or balls that stick out far, this can make it harder to smooth your fault line.

Add A Metallic Touch To Your Sprinkle Fault Line Cake

Add a metallic touch to your cake to really make your fault line pop!

Painting the edge of the fault line really makes it almost seem like it’s exploding. It also bright the cake up, and creates a great contrast with the black cocoa frosting.

I used edible art paint on this cake, which is so easy to use. However, you could also use a mixture of luster dust and a clear alcohol too!

I chose to use gold based on the sprinkles I used. Silver accents could look really cool with other sprinkle blend though!

Leaving Texture On The Top Edge Of The Cake

As I decorated this cake, I decided to leave a textured edge around the top of it. This style became super popular after it was used on Prince Harry and Meghan Markle’s wedding cake.

I liked the way it looked on this cake, because it seemed to echo the whole rocky, geological theme. The rough edge looked kind of rugged, and I loved how it kind of tied the whole cake together.

Let Me Know What You Think!

If you try this sprinkle fault line cake recipe, please tag me @chelsweets and use the #chelsweets so that I can see your amazing creations!

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