In a small bowl, make a dressing with the yogurt, sugar, cardamom and citrus juice. Pour this over the melon cubes, fold in slightly and serve immediately.
The melon cubes should be well chilled for this salad. Cantaloupe are best, but are also possible with all other types of melon that have greenish-white or orange pulp.
If you don`t use Greek yoghurt, you should take natural yoghurt with 3.7% fat and let it drip out a little.