This is one of the best known French classical dishes, and is of very ancient origin. There are various kinds of blanquettes, but I give the authentic one known as “à l’ancienne.”
Put the veal in a saucepan and cover with the water. Add the salt. Bring to the boil gradually and skim very carefully. When the scum has ceased to rise, add the vegetables and herbs. Bring to the boil, put the lid on the saucepan, leaving a small opening, and simmer gently for 1 hour or a little more. The meat should be tender and yet firm. Meanwhile, boil the mushrooms in a little water over a quick fire till tender, and cook the onions in butter, but without browning. Make the sauce by putting the butter in a saucepan and, when melted, adding the flour and stirring over a very slow fire for 10 minutes, but without browning in the slightest. Then dilute gradually with the strained veal stock, stirring well. Bring to the boil, add the mushroom peelings, and a few peppercorns. Skim carefully, and add the egg liaison—made by mixing the eggs in a basin with the lemon juice, a few tablespoons of cold stock, and adding gradually a few tablespoons of the warm sauce. Add the cream. Now put the pieces of veal in a clean saucepan, pour the strained sauce over them, add the mushrooms, and cook for a few minutes without boiling. Just before serving add the onions. To dish up, put the pieces of veal in the centre of the dish, pour the sauce over them and garnish with the mushrooms and onions. Sprinkle with chopped parsley.