Remove the green leaves from 15 artichokes and soak them in cold water for an hour. Boil in salted boiling water and let them cool. Remove some of the artichoke heart with a sharp knife and add to the sauce,* prepared as follows. Melt 1 spoon butter in a saucepan, stir in 1 spoon flour, and dilute with 1½ glasses bouillon. Boil thoroughly, stirring, and add nutmeg, a little lemon juice, and 2–3 beaten egg yolks, diluting them first with a little of the cooled sauce. Cook, stirring, until the sauce begins to emit steam. Add the artichokes to the sauce, heat, and serve.