Place the mangoes & peaches in a deep bowl & blend with the immersion blender.
Add the remaining ingredients & blend well again till thoroughly mixed. Adjust sugar if required.
Turn into a freezer container, & whisk every hour to distribute the crystals, at least 4-5 times. (or use the instructions on your ice-cream maker; I don't have one so I use elbow grease!!)
Leave to set for 6-8 hours, or preferably overnight.