Chop up one sound onion and two well-peeled shallots; brown them in a saucepan with one ounce of butter, for five minutes, then add double the quantity of finely minced mushrooms and a grain of garlic; season with half a tablespoonful of salt and a teaspoonful of pepper, and finish with a tablespoonful of chopped parsley. Cook ten minutes longer, and then let it cool.