Cut the melon into large slices. Remove the skin from the flesh and cut the flesh into pieces. Peel and chop the onion. Roughly pluck the bread. Pour melon, onion, bread and nectar into a large bowl and blend finely with a hand blender.
Season to taste with vinegar, salt and pepper. Clean, wash and finely dice the cucumber, celery and paprika and stir into the gazpacho. Cover and chill for at least 1 hour.
Wash the herbs and shake dry, pluck the leaves and chop them finely. Stir into the gazpacho just before serving.