Boil 8 eggs for 6-8 minutes, 1 egg for about 10 minutes. Meanwhile wash and dry the herbs, pluck the leaves and chop half of them finely. Quench the eggs and keep 8 eggs warm. Peel the hard-boiled egg, cut it in half, remove the yolk, pass it through a fine sieve into a bowl and mix with the raw egg yolk and mustard.
Using a whisk, beat the oil and vinegar drop by drop into the egg yolk mixture until a mayonnaise-like mixture is formed. Put one part of the herbs aside for garnishing, puree the rest with the cream in a mixer.
Finely chop the remaining egg white. Stir the herb cream, chopped egg white, chopped herbs and milk into the egg yolk mixture. Season to taste with salt and pepper. Peel the 8 eggs and cut them in half lengthwise. Arrange green sauce and eggs on plates and garnish with the remaining herbs.