How to make a sprinkle fault line cake

Ready to get totally on trend and try creating CD&S's fabulous fault line cake with sprinkles?

This marvellous, messy and simply magnificent cake decorating style has come into our lives and shaken the foundations of what we know and love about cake decoration. When it comes to earth-shattering innovations in cake decorating, sprinkle fault line cakes are off the Richter scale!

Terrible earthquake puns aside, fault line cakes with sprinkles are all the rage at the moment and we couldn't love them more. Creating craters of cake filled with even more deliciousness from buttercream and sprinkles, all part of an ideal style to personalise and go all out with colour and your imagination? Try and stop us!

Read on for CD&S's spectacular sprinkle fault line cake tutorial and don't forget to check out extra fault line cake inspiration at the end!

Sprinkle fault line cake

By Karen Keaney

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You will need

For the buttercream:

500g unsalted butter at room temperature
1kg sifted icing sugar
Flavouring of your choice
A couple of tablespoons of liquid, either cooled boiled water or UHT milk
Colours of your choice
Stand mixer

For the cake:

2x 6in round cakes
800g yellow buttercream
250g pink buttercream
250g blue buttercream
Brightly coloured sprinkles
25g each of yellow and blue sugarpaste 
Gold lustre or highlighter
Confectioner’s glaze
Piping gel

8in round cake board
Palette knife
Side scraper
Pro froster 
Piping bags and nozzles (any nozzles will work; I have used the closed star style)

Make your buttercream

  • Begin by using the whisk attachment on your stand mixer. Add the butter and beat on high until it becomes paler in colour.
  • Turn the mixer to low and begin adding the icing sugar a cup at a time (if you have a cover/shield for the top of your mixer it’s a good idea to use it now).
  • You can add a tablespoon of liquid once the mixture starts looking dry.
  • Add a colour and flavouring.
  • Once all the ingredients are added beat on high for about five minutes.
  • Switch to the paddle beater and beat for another five minutes, this helps eliminate the air from the buttercream.


Fill and stack your cake

1. Split and fill your cakes straight onto the 8in cake board. 

fault line cake with sprinkles step 1

2. Once stacked, trim off any parts of the cake that protrude out - this gives you a nice base to begin applying the buttercream.

fault line cake with sprinkles step 2

Apply buttercream

3. Using the palette knife, apply a thin coat of yellow buttercream all over the cake; this is called a crumb coat and seals in all the crumbs so that they don’t make their way into your final coat. Refrigerate the cake for about 15 minutes to allow the buttercream to firm up.

fault line cake with sprinkles step

4. Apply a second coat of buttercream all over the cake.

fault line cake with sprinkles step 4

5. Set the pro froster to the correct height for your cake.

fault line cake with sprinkles step 5

6. Use the pro froster to smooth the top and sides at the same time. This will give you straight sides and top.

fault line cake with sprinkles step 6

Apply the sprinkles

7. Place your cake on a wire rack over a baking tray. Apply the sprinkles to the middle part of your cake only, the tray underneath will catch the sprinkles that fall off.

fault line cake with sprinkles step 7

8. Brush away as much of the spilled sprinkles from the bottom as possible. Refrigerate again until firm.

fault line cake with sprinkles step 8

Prepare the fault line

9. Apply the remaining yellow icing with a piping bag above and below the sprinkles. You need to be generous with the icing so you don’t scrape off the sprinkles in the next step.

fault line cake with sprinkles step 9

10. Smooth out the buttercream using a side scraper. Take care not to get too close to the sprinkles.

fault line cake with sprinkles step 10

Decorate the top

11. Apply a layer of buttercream to the top of the cake and level using the palette knife.

fault line cake with sprinkles step 11

12. Insert the nozzles into the piping bag and fill the piping bag with blue icing. Pipe swirls of icing on the top of the cake as shown.

fault line cake with sprinkles step 12

13. Repeat for the pink icing, but pipe smaller swirls in between the blue.

fault line cake with sprinkles step 13

14. Pipe one large blue swirl in the middle.

fault line cake with sprinkles step 14

15. Fill in the top with little pink swirls.

fault line cake with sprinkles step 15

16. Add some sprinkles all over the top.

fault line cake with sprinkles step 16

17. Clean up the board with a paper towel.

fault line cake with sprinkles step 17

Make the fault line

18. Mix some gold lustre or highlighter with some confectioner’s glaze and paint it along the top and bottom edge of the fault line.

fault line cake with sprinkles step 18

19. Make some yellow and blue balls by rolling small pieces of the coloured sugarpaste in your hands.

fault line cake with sprinkles step 19

20. Sprinkle the balls on the cake, you can also add some into the fault line.

fault line cake with sprinkles step 20

Finishing touches

21. Finish the board off with a ribbon and bow (you know the rules when it comes to using ribbon on cake).

fault line cake with sprinkles step 21

22. Pipe some piping gel or a very thin layer buttercream on the board and spread some sprinkles onto it.

fault line cake with sprinkles step 22

More fault line cake inspiration

Fault line cakes with sprinkles a little too bright for you? No matter, we've found some stunning inspiration to give you just a taste of the gorgeous potential of the fault line cake trend!

The way the cookie crumbles

cookie fault line cake

Cake by @paintingwithbuttercream

We challenge anyone to look at this incredible fault line cake with cookies and not find their mouths watering uncontrollably! Fault line cakes don't have to be all about colour coordination or excessive brightness, you can use this incredible versatile style to draw attention to the flavours of your cake.


Fault line cake inspiration

Cake by @yyccakeclub

This incredible creation ticks all the right boxes to make a flawlessly fashionable statement. Totally on trend fault line cake style? Check. Chic and suave geometric pattern? Check. Metallic elements mixed with natural ones? Check. Delicious extra macaroon morsels? Check! This clever style keeps you constantly looking again to find extra stunning elements you may have missed on first glance. 

Stacked to the rafters

fault line cake inspiration

Cake by @luliscakery

We can pretty comfortably conclude that macaroons and fault line cakes go together like, well, fault line cakes with sprinkles! This design really makes the most of the fault line trend and uses it to create a tremendously tall cake bursting with delicious treats. The subtle colouring and clever detailing around the edges of the fault line really show just how impressive fault line cakes can be. 

We could go on and on and, here at CD&S, we truly love innovative cake decoration to a fault! 

Be sure to keep an eye out for more totally on trend designs like this sprinkle fault line cake in CD&S and, if you're looking for more decorating inspiration right here, be sure to check out our ultimate guide on how to pipe cupcakes to the perfect finish and ensure your cupcakes are on point, every time. 

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