Wash the fish, dab dry. Let the fish simmer in boiling water for about 20 minutes. Take the fish out and let it cool down. Meanwhile, boil eggs in boiling water for about 10 minutes until hard. Quench cold and peel. Halve the eggs, remove the yolks from the halves and chop
Wash parsley, shake dry, pluck leaves from the stalks and chop coarsely. Remove seeds from dates and chop finely. Mix dates, parsley, egg yolks, oil and lemon juice, season with salt and pepper. Dice tuna, mix with sauce and serve