beat the egg white in a shallow bowl and spread out the caster sugar on
a baking sheet or tray. Dip the grapes and
the holly or bay leaves into the egg white, or use a paintbrush. Shake
off the excess, then coat in the sugar. Set aside to dry for at least 10
mins, ideally about 30 mins.
you’re ready to decorate, make the frosting. Put a large bowl over a
pan of simmering water, making sure the bottom of the bowl does not
touch the water. Put the egg whites and icing sugar into the bowl and
whisk for 5-7 mins until you have a thick, very glossy frosting. Use a
spatula to clean around the edges of the bowl every so often as you
whisk. Scoop the frosting onto the top of the cake and spread it around
with a flat-edged knife, swirling as you go to create a snowy effect
(see Knowhow, below).
the clementines, figs and kumquats, then arrange on top of the frosted
cake with the physalis, frosted grapes and leaves. Fix a ribbon around
the base and leave the cake somewhere cool – but not the fridge – until
your guests arrive.