2 hr 50 min
Bring 2 cups water to a boil in a saucepan. Add 1/3 cup large tapioca pearls, partially cover and simmer over medium heat, stirring occasionally, until the pearls are translucent, about 40 minutes. Stir in 3/4 cup unsweetened coconut milk, 2 tablespoons sugar and a pinch of salt until dissolved. Transfer to a bowl and add 1 teaspoon vanilla extract. Let cool, then cover and chill at least 2 hours. Top with diced mango and drizzle with mango nectar.