Drain the coconut of milk. Crack each open using a hammer and chisel and scoop out the soft flesh taking care not to include any of the brown fibrous exterior.
In a food processor blend the mango, coconut, coconut cream and lime juice together until smooth.
Place in a container and freeze for 2 hours. When the edges have frozen, return to the processor and blend again. Return to the freezer for a further 3 hours before serving.
Serve with fresh mint leaves.
Note : Drinking coconuts are available from the refrigerated section of most leading green grocers. They are usually wrapped in plastic film and have a white exterior.