Line baking sheet or tray with plastic wrap. Arrange mango slices in a single layer on baking sheet. Cover with plastic wrap and freeze until firm.
In blender, combine peach nectar and coconut milk; add peaches and mango. Cover and blend until smooth.
If desired, garnish each serving with lemon peel and mint.
Notes
When you're shopping for a ripe mango, look for one that's a rich green or yellow color and tinged with red. It should have a sweet fruity smell and feel fairly firm when gently pressed.