1 envelope (1 tablespoon) unflavored gelatin
2 cups fresh mango purée (about 2 peeled and pitted mangoes) plus mango slices for garnish (i used 3)
1/3 cup sugar （i used half of it , of course:)
1/2 teaspoon vanilla extract
1 cup plain yogurt
1 cup well-chilled heavy cream
In a small saucepan sprinkle the gelatin over 1/4 cup cold water, let it soften for 1 minute, and heat the mixture over low heat, stirring, until the gelatin is dissolved. In a blender blend together the mango purée, the sugar, and the vanilla, add the gelatin mixture, and blend the mixture well. Transfer the mixture to a bowl and stir in the yogurt. In a chilled bowl beat the cream until it holds stiff peaks, fold it into the mango mixture gently but thoroughly, and divide the mousse among 4 dessert glasses. Chill the mousses for at least 4 hours or overnight. Garnish the mousses with the mango slices.