German Sauce
Make brown sauce, add ½ can halved button mushrooms and 1 tablespoon of reduced vinegar, and season with salt and pepper.
German Egg Sauce
Mix 3 beaten egg-yolks with 1 teaspoon of flour, 1 scant cup of cream or milk, 1 tablespoon of butter, and 1 tablespoon of lemon juice, season with salt and pepper, and beat vigorously, until thickened, over a hot fire, but do not let the sauce boil at all. Add 1 hard-boiled egg, chopped fine, and 1 tablespoon of minced parsley before serving.