In a large saucepan, add the water, rice syrup, coconut milk, cocoa powder, and salt. Whisk to combine.
Heat on a medium heat, all the while whisking, until the mixture comes to a boil. Continue to cook for about 2 minutes, ensuring that you continue to keep whisking.
Remove from the heat and add the chocolate and vanilla. Stir until chocolate is melted.
Strain mixture into an airtight container and chill for at least 3 hours (preferably overnight).
Churn in your ice cream maker then scoop into a container and freeze for 2-3 hours until hardened.