Mix the sugars and almonds in a large
bowl, then rub in the vanilla seeds until even.
Make a well in the middle, then tip in the
eggs and citrus juice. Cut the wet ingredients
into the dry with a cutlery knife. Dust the
surface with icing sugar, then knead the
marzipan briefly with your hands to a
smooth dough. Don’t overdo it as the paste
can get greasy. Add a bit more icing sugar
if it seems too wet. Shape into a ball, then
wrap and keep in a cool place until ready to
cover the cake. Can be made up to 2 days
Lift the cake onto a cake board or plate,
then use a pastry brush to cover evenly with
a thin layer of jam. Dust the work surface
with more icing sugar, then roll the marzipan
into a circle about 40cm across, dusting
underneath the marzipan with more icing
sugar and turning it a quarter turn after every
few pushes of the rolling pin.
Flip the top of the circle back over your
rolling pin so you can see the underside of
the marzipan, then lift the pin up and lift the
marzipan over the cake. Stop once you can
see that the edge of the marzipan nearest
you is about level with the bottom of the
cake. Flop the front of the marzipan down.
Smooth the paste over the cake using the
palms of your hands, then trim with a sharp
knife. If any cracks appear, simply pinch the
paste back together and smooth. Leave to
dry for at least 24 hrs, or up to 3 days, before covering with icing.
How long does homemade marzipan keep? Although homemade marzipan contains raw eggs, the amount of sugar, and lack of moisture, prevents bacteria growing when left at room temperature, so your cake should last for 1-2 months iced. The most important thing is that you don't scrimp on drying time – once you’ve covered your cake in marzipan it should be left to completely dry out, before you then cover it with icing. If you want to make marzipan before you are ready to cover your cake, then wrap it well in cling film and keep in a fridge for up to a week – as wrapped in a ball it will still contain a little moisture. As it contains raw eggs it shouldn’t be given to anyone in an at-risk group, including pregnant women, the elderly, the unwell and the very young. You can make a cooked marzipan, which carries no risks. It is a little softer, and harder to work with, but a good substitute if you are at all worried.