The marzipan layer on a wedding or Christmas cake helps to trap moisture in the cake and stop it staling – plus it provides a smooth surface so that the final icing is neater.
-Thin the jam with a little water so that it’s the consistency of double cream and bring this to the boil. Pour the hot jam through a sieve into a bowl, pressing any fruit pieces through to extract the liquid. Leave until warm before using.
– If the cake has peaked in the middle during baking you will want to carefully slice it flat, but if the cake is just gently domed then there’s no need.
-Lightly knead a generous amount of marzipan so that it’s smooth and then roll it out on a worktop dusted with icing sugar. Roll the marzipan into a disc about 1cm/½in thick and 1-2cm/½-1in wider than the diameter of your cake (check the marzipan isn’t sticking to the worktop by dusting underneath it again with icing sugar).
-Brush the top of the cake with the sieved jam and then leave a few minutes for it to set. (This helps the marzipan stick to the cake.) Turn the cake upside down onto the marzipan and wiggle it gently so the top is stuck firmly.
-Trim any excess marzipan leaving a 2cm/1in border. Using a knife, gently press up into the gap caused by the curve of the cake and then scrape it up smoothly so that it’s level with the side of the cake.
-Carefully turn the cake the right way up and you should be left with a perfectly flat top surface and straight sides.
-Brush more of the sieved jam around the sides of the cake and onto the edge of the top disc of marzipan.
Knead the marzipan trimmings along with some extra marzipan until smooth and roll it into a strip slightly wider than the height of the cake. (You can also roll two or three strips, each a half or a third of the circumference, as this is easier to manage.)
-Trim one end of the marzipan straight and press it firmly against the cake so that the straight edge runs along the bottom and the rough edge slightly peeks over the top. Trim away any excess from the marzipan along the top of the cake. If you are covering the sides using two or three strips smaller strips, repeat with the next strip, joining the straight cut ends neatly.
-Smooth the cake with a cake smoother.
-Allow the marzipan to dry for 4-5 days at room temperature before applying the icing.