Heat oven to 350F with a rack in the middle position
In a bowl, mix together the sugar, salt and cardamom; set aside
In a large pot, stir together the coconut milk and 2 1/2 cups of water; bring to a boil over medium-heat
Once the water and milk is boiling, stir in the rice, sugar mixture and lime zest. Cut the lime in half and squeeze half the lime into the mixture.
Cover and transfer to the oven. Bake for 1 hour, until rice is tender and creamy
Take the rice pudding out of the oven and add the vanilla extract and mix well
Let cool for 15 minutes. Serve in individual bowls at warm or at room temp
Garnish with more ground cardamom and chopped mango and/or chopped pistachios