To prepare jam, combine 1/3 cup water and 3 tablespoons sugar in a small saucepan over medium heat. Cook 3 minutes or until sugar dissolves. Add 1 cup chopped strawberries, and bring to a boil. Reduce heat, and simmer 10 minutes or until mixture is syrupy, mashing strawberries with a fork. Remove from heat, and stir in remaining 1 cup chopped strawberries. Pour into a bowl, and cool completely. Cover and chill.
To prepare crème, sprinkle gelatin over whole milk in a small saucepan; let stand for 10 minutes. Scrape seeds from vanilla bean, and add seeds and bean to milk mixture. Cook the milk mixture over medium-low heat 10 minutes or until gelatin dissolves, stirring constantly with a whisk. Increase heat to medium, and add 6 tablespoons sugar, stirring until sugar dissolves. Remove from heat. Stir in buttermilk. Remove and discard vanilla bean. Spoon about 1/2 cup buttermilk mixture into each of 6 small glasses. Cover and chill 6 hours or until set. Top each serving with 3 tablespoons berry jam. Garnish with mint sprigs, if desired.