It’s best to work with chilled or indeed slightly frozen cake layers. So make sure you’ve baked them well in advance. All fillings should be freshly whipped and room temperature. 

You will need:

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Method:

•  Using a cake leveller or bread knife, remove the dome from each sponge. Make sure they are all the same depth (around 1”). 
  
  
•  Put the non stick mat on the turntable. Place a cake board or drum the same size as your cake on top. If the mat is sticking out from underneath then trim to a few millimetres within the board or drum, otherwise it will get in the way while you’re working. Put a dab of buttercream or ganache on the cake board/drum, place your first sponge, brown side down, on top and press down slightly to ensure it sticks in place. If required, brush a little sugar syrup on the surface and give it a few moments to soak in.

•  If you’re adding a loose filling such as jam or caramel, load a piping bag with some of your buttercream or ganache and pipe a couple of rings, approximately 1cm thick, round the edge of the sponge and spoon the filling within. Ensure it doesn’t exceed the height of the piped rings. This acts as a sort of dam to hold the filling within. If you’re not adding a runny filling, evenly spread the buttercream or ganache over the entire sponge so it’s approximately 1cm thick. Go right up to the edge.

•  Place the next sponge on top and repeat as necessary, however, do make sure the final sponge is the brown, not trimmed side up, so flip it if need be.

•  Once all the sponges are assembled, gently press on top to ensure the cake is level and free of air bubbles. Brush a little sugar syrup on top if need be. Wrap the whole thing in clingfilm so it doesn’t dry out and chill until you’re ready for the next step.