In a medium pot, stir together the rice, 1 1/2 cans coconut milk (reserve remaining coconut milk for Round 2 Recipe Coconut Chicken Soup), sugar, and lime peel. Put the pot over medium heat, bring it to a simmer, and cover. Cook until the pudding becomes very thick, 20 to 25 minutes.
While the pudding is cooking, toast the shredded coconut in a dry skillet over medium heat until golden brown.
After the pudding has cooled 10 minutes, stir in the vanilla. Serve the rice pudding topped with diced mango and sprinkled with toasted coconut.