Wash and peel the asparagus, cut off the woody ends. Cook the asparagus in boiling salted water with lemon juice and 1 teaspoon butter for about 20 minutes. In the meantime, clean and wash the mushrooms and cut them into thin slices.
Dice the ham. Heat the oil and fry the mushrooms in it. Add the diced ham. Cut salmon into fine strips. Heat remaining butter in a pot. Sauté the flour in it. Deglaze with 1/2 litre asparagus water and milk and boil up while stirring.
Season to taste with salt and pepper. Divide the sauce into 3 parts. Mix one part with mushrooms and ham, the second part with salmon and dill. Wash the chervil, remove the leaves and add to the rest of the sauce.
Remove the asparagus and arrange on a preheated plate. Pour a little chervil sauce over the asparagus. Garnish with lemon and chervil. Add the sauces separately. Smoked ham tastes good with it.