I kept this dessert kid-friendly, using rum extract, but there's no reason that if you're feeding grown-ups, you couldn't use rum.
We call the pit the "mango bone" in our house; it's a favorite treat of my youngest daughter. When you cut up the fruit, save the mango bones and simmer them in the syrup to intensify the mango flavor. You will need an ice cream mixer for this recipe.
1 cup sugar
1 cup water
2 cups cubed mango (from 3 to 4 fruits), pureed, saving the mango bones
2 teaspoons lime juice from 1/2 lime
3 or 4 mint leaves, chopped
1 teaspoon rum extract (for alcohol-free version) or rum
In a saucepan over moderate heat, place sugar, water and mango bones. Let come to a boil and cook, stirring occasionally until sugar is dissolved.
Remove from heat, add lime juice, mint leaves, puréed mango and rum extract and let cool. After at least 15 minutes, strain through a sieve and pour in container of ice cream machine. Follow manufacturer's instructions from here. Store leftovers, those precious leftovers, in the freezer. Trust me, they won't last long.