Place the star fruit (count out 3 slices per person) in a pot on the stove. Add the orange juice. Stir well and turn heat to high until juice begins to boil. Then turn down to medium.
Allow to simmer for 10 minutes, or until star fruit has softened enough to easily cut into with a spoon. Now and then you can gently move the slices around and turn them over so they all get cooked more or less equally. Remove any more brown seeds that may loosen and surface.
When star fruit is nearly done, adding the sugar/sweetener and stir to dissolve. Remove pot from heat.
Add the mango puree, stirring well to incorporate.
Do a taste-test for sweetness, adding more sugar if needed (how sweet it is will depend on the ripeness of the fruit/juice you're using). If it happens to be too sweet for your taste, add a squeeze of fresh lime juice, or a little more orange juice.
When you're happy with the taste, portion out 3 star fruit slices per bowl with enough sauce to surround the fruit (it should still be warm from the pot). Top each bowl with a sprinkling of pomegranate seeds or cherry pieces. Drizzle over some coconut milk and serve!
This dessert is also excellent when given a final topping of whipped cream or vanilla ice cream.