Heat cream, milk, and orange zest until boiling, then infuse for 10 minutes.
Whisk egg yolks and sugar together and then whisk in the warm cream mixture.
Stir in orange juice and cook until thickened without boiling, then chill.
Churn two-thirds of the crème anglaise in an ice cream machine and freeze.
Sieve the remaining crème anglaise and chill in the fridge.
Preheat the oven to 180°C.
Grease four ramekins with butter and coat with a little grated chocolate.
Melt the chopped chocolate and butter in a heatproof bowl over simmering water.
Remove from heat and whisk in ground almonds, egg yolks, cornflour, and star anise.
Whisk egg whites to stiff peaks, add sugar, and fold into the chocolate mixture.
Fill ramekins halfway with mixture, add a truffle, and top with more mixture.
Bake for 10 to 15 minutes until risen and slightly wobbly.
Serve fondant with grated chocolate, orange crème anglaise, and orange ice cream.