Place the cream and milk in a saucepan and bring just to the boil. Place the chocolate in a small heatproof bowl and pour over the hot cream. Stir together until the chocolate melts, then leave to cool slightly.
Whisk together the 75 g (3 oz) sugar, the orange rind, eggs and egg yolks in a separate bowl, then gradually whisk in the cooled chocolate mixture.
Place 6 ramekins in a deep baking tin. Divide the mixture among the ramekins, then pour boiling water into the tin until it comes halfway up the sides of the dishes. Bake in a preheated oven, 160°C (325°F), Gas Mark 3, for 15–20 minutes until just set but still with a slight wobble in the centres. Leave to cool, then chill for at least 2 hours or overnight.
When ready to serve, whip together the cream and remaining sugar until soft peaks form. Spoon a little of the cream into each dish and top with strips of candied orange peel or finely grated orange rind.