Wash limes thoroughly with hot water and rub dry. Finely grate the zest of one lime. Peel the remaining lime with a julienne lime nipper. Halve limes and squeeze juice.
Mix coconut milk, cream, yoghurt, sugar, vanillin sugar, lime juice and lime zest. Keep cold. Halve melons. Remove the seeds with a tablespoon. Cut out the flesh of one half of each melon with ball cutters of different sizes.
Mix melon balls. Put one half of each melon ball into a pitted melon half. Fill up with the coconut cold peel. Sprinkle with lime julienne and serve decorated as desired with mint leaves and nasturtium.