Method

• 1.
  For prunes, combine all ingredients in a bowl, cover with plastic wrap and leave to soak at room temperature overnight.
• 2.
  The next day, place chocolate in a heatproof bowl set over a saucepan of simmering water, (don't let the bowl touch the water), stirring until melted and smooth. Remove from heat and allow to cool. Warm the cream in a pan, then mix into the chocolate until smooth. In a separate bowl, beat eggwhites and sugar with electric beaters until soft peaks form. Whisk yolks into chocolate mixture, then, in two batches, gently fold through the beaten eggwhites.
• 3.
  Place the prunes in the base of a deep, glass trifle dish, pressing them against the sides. Pour over the mousse, then cover and chill for 2-3 hours until set.
• 4.
  Top with chocolate shavings to serve.