1. In a saucepan, bring the coconut or soy milk, orange juice, orange zest, and vanilla seeds to a boil.
2. In a bowl, whisk egg yolks, sugar, and cornstarch with a hand whisk. Pour the hot milk mixture into the egg yolk mixture, beating briskly. Mix well and return to the pot. Cook, mixing constantly until thickened.
3. Remove from the heat, add the chopped chocolate, and mix well. Add the liqueur and mix. Transfer the hot mixture to a shallow dish or bowl. Cover with plastic wrap and refrigerate for one hour.