Add water,prunes, and one cup of sugar to a saucepan and bring to a boil. Reduce heat and simmer for 10 minutes until the prunes are soft and expand. Strain out the water and set aside to cool.
Whisk egg yolks in a bowl with the remaining half cup of sugar, then set aside.
Add cream and milk to a medium saucepan and heat until simmering. Remove from heat.
Slowly pour one cup of milk into the yolks, whisking until combined. Then, pour the yolks slowly back into the saucepan of milk and lightly whisk. Continue heating until the mixture thickens. Add a pinch of salt, then remove from heat.
Add the prunes and milk mixture to a blender. Process until you achieve the desired texture. I only blend for a few seconds to get chunks of prune in the ice cream.
Cool the ice cream custard in the fridge for at least 3 hours, preferably overnight.
Churn using an ice cream maker per the manufacturer's instructions, then scoop into a container and freeze for 2 hours.