Chop the chocolate into small pieces and put 3/4 into a heatproof bowl.
Put this bowl over a saucepan of simmering water and allow to melt gently. Remove from heat and be careful not to allow any steam or water to get into the chocolate.
Stir in the remaining chocolate and spread along the stiips of acetate or baking parchment.
Allow to set slightly and then join the two edges together to make a teardrop and place on a baking tray that has been lined with baking parchment and spoon chocolate into the bottom of the teardrop and allow to set.
Method for Parfait
Put eggs yolks, sugar, orange juice and rind into a heat proof bowl.
Place over a pot of simmering water and whisk until thick.
Remove from heat and with an electric whisk, whisk for 5 minutes until the mixture is really pale and cold.
Fold this mix into the cream and fill the teardrops and freeze.