Mix eggs, milk, flour and salt with the whisk of the hand mixer to a smooth pancake batter. Rinse parsley and oregano, dab dry and chop finely. Stir the herbs into the batter. Bake four thin pancakes in a layered pan without fat. Roll up the pancakes. Peel and wash the celery and carrots, first cut into long thin slices, then into fine strips. Halve the leek lengthwise and cut into strips.
Blanch the vegetable strips in bubbling salt water for 1 minute and rinse in cold water. Drain the vegetables on a sieve. Cut the pancake rolls into thin slices. Bring the vegetable stock to the boil and arrange it on four portion plates or soup bowls. Add vegetable strips and pancake rolls to the soup as garnish. Sprinkle with oregano leaves