Christmas fault line cake

Add a crumb coat of buttercream to the cake using a palette knife. Smooth the sides with a cake scraper; it doesn't need to be perfect as it will be covered up later.

Pop the cake in a cake box lid; this stops all the sprinkles from falling everywhere. Using your fingers, scoop up the sprinkles and gently press them around the centre of the cake. Keep the sprinkles as small as possible or they will get in the way of smoothing the buttercream out later. Clean the cake drum, making sure you keep the remaining sprinkles.

Put some buttercream in a piping bag, then snip the end off. Begin by piping the bottom wavy fault line, as pictured, then fill in the top and bottom gap.

Using a cake smoother, very gently begin to smooth off the buttercream; don’t put too much pressure on it. Try to go around the cake in one motion, as this will ensure the cake becomes smoother and will stop lines appearing from the scraper.

Once it's all smooth, add a little buttercream on top and smooth out again. Colour some buttercream to match the cake sprinkles, then place them into piping bags fitted with a 2D nozzle. Pipe small swirls on top of the cake in all your coordinating colours, then add some sprinkles.

Now you can add larger sprinkles to the fault line gap and press some into the buttercream. Put the cake in the refrigerator for at least 30 minutes – it needs to be really firm for the next stage.

Mix some gold lustre dust and rejuvenator together to form a thick paint. Once the cake is firm, paint the top and bottom edges of the buttercream fault line with the gold paint, to finish.