Cut the peeled and pitted tomatoes into 1 cm cubes, put some of them aside for decoration.
Peel off the pulp from the melon, remove the stones and finely chop everything. Peel the cucumber, remove the seeds, cut the pulp into pieces.
Puree the tomatoes, cucumber, melon and the green of the spring onions in a blender until smooth. Finally, stir in the remaining diced tomatoes and add the chopped mint. Season to taste with pepper and salt. Refrigerate.
This cold soup has a special aroma if it is allowed to steep for 12 hours.