Place the chocolate
in a heatproof bowl placed over a saucepan of
simmering water and leave to melt slowly,
stirring occasionally. Leave to cool slightly.
Pour the cream into a small bowl and whip until soft
peaks form.
Gently stir the brandy and coffee
essence into the chocolate. Mix together gently
until blended, then fold in the whipped cream with a
metal spoon.
Briskly
whisk the egg white in a small bowl until stiff,
then fold in the chocolate mixture with a
metal spoon.
Mix gently. Spoon into 4 tall glasses
and chill for at least 2 hours.