For the strawberry coulis: In a medium saucepan over medium heat, add the strawberries, sugar, lemon juice and vanilla bean. Bring to a boil until fruit is softened. Pour cooked liquid into a blender, blend and strain. Set aside.
For the flowers: Melt the chocolate, and pour and spread over a 4-by-18-inch piece of acetate. Allow the chocolate to set slightly then cut small leaf-shaped petals out of the chocolate with a paring knife. Leave the chocolate on the acetate, bend the acetate and place between two cake pans to hold in a crescent shape. Allow to set then move to the freezer for 15 minutes before breaking into petals.
Pour a circle of chocolate and allow it to set. Dip each set chocolate petal in a bit of melted chocolate and adhere to the base. Once half of the sphere of petals is assembled place the dessert inside. Assemble the remaining chocolate petals and chill slightly to set.
When ready to serve, garnish with mint and place into a deep bowl. Warm the strawberry coulis and pour around the dessert. The warm coulis will melt the base of the chocolate flower and create a blooming effect!