Put the eggs in boiling water and boil them hard for about 9 minutes. Drain, rinse and peel. Wash herbs, shake dry. Finely chop parsley and lemon balm. Cut chives into fine rolls.
Halve 6 eggs. Remove the egg yolks and pass through a fine sieve. Chop the egg whites finely. Mix yoghurt, cream, mustard and egg yolk. Season to taste with salt and pepper. Mix 1 teaspoon egg whites and 1 teaspoon chopped herbs.
Stir the rest of the herbs and egg white into the cream. Cut 1 egg into slices. Put 1 slice of bread on 4 plates. Add some egg salad and sprinkle with herb and egg white mixture. Garnish with parsley and egg slices.
Add the rest of the salad garnished with lemon balm.