Frozen Watermelon Souffles
Place the melon pulp and lime juice in a blender and puree (or puree in a bowl with an immersion blender0. Add the mascarpone and puree until smooth, transfer to a bowl. Separate the eggs. Place the yolks, sugar and vanilla sugar in a metal bowl and beat over a pan of simmering water until thick and creamy. Place the bowl over a bowl of ice water and stir occasionally until cool.
Fold the cold custard into the melon puree. Beat the egg whites until stiff. In a separate bowl, beat the cream until stiff. Gently fold the cream and the egg whites into the into the melon mixture. Pour the cream into ramekins and freeze at least 3 hours.
About 30 minutes before serving, take the molds out of the freezer and place them in the refrigerator to thaw slightly. Garnish and serve with bonbons.