Whisk the egg yolk with the caster
sugar and vanilla paste until pale. Add the
mascarpone and cream, then beat with
an electric whisk until smooth and thick.
Put the Kahlua and coffee in a bowl and
dip in enough sponge fingers to cover the
bottoms of 2 small bowls or ramekins.
Cover with half the creamy mixture,
repeat with some more soaked biscuits,
topping with more creamy mixture, until
your dishes are full. Dust with a little
cocoa powder and chill for at least 2 hrs
For the honeycomb, oil a baking tray
or tin or line with a non-stick mat. Gently
heat the sugar and honey with a splash
of water in a heavy-based pan until
melted. Increase the heat and bubble to
a good caramel colour, then lift off the
heat, whisk in the bicarb and tip onto the
baking tray to cool. Once cold, crush with
a rolling pin or thinly slice into shards,
and scatter a little over the tiramisus to
serve. Leftover honeycomb will keep for
a week in an airtight tin.