eel the skin of the sweet potatoes, quartered them and steam until soften
Mash sweet potatoes while still hot
Into a mixer bowl, pour orange juice and milk
Add in mashed sweet potatoes, mix until well combine
Pour mixture into ice cream bowl and freeze for 2 hours
Meanwhile, soak sultanas in hot boiling water
Take out ice cream from freezer, pour it into a blender and turn on blender on high until ice cream smooth again.
Back into the bowl and freeze for another 2 hours.
Take out ice cream from freezer, scoop it into blender, and pour sultana mixture into the blender as well. Mix in high speed.
Pour back into the bowl and freeze. Repeat this blending step and freeze, for twice more.