Plunge the whole round tenderloin into boiling water, to cover, in a deep skillet, and let it boil hard 2 minutes, then reduce the heat and let it simmer, closely covered, for 3/4 of an hour. Then pour off the water and keep it for the gravy. Put 4 tablespoonfuls of butter, or lard, in the skillet and fry the tenderloin, closely covered, until a rich brown. When done remove to a hot platter and keep warm. Add 4 tablespoonfuls of flour to lard in skillet, rubbing it smooth ; then pour in gradually enough of the reserved juice to make gravy of the proper consistency. Add mushrooms, previously prepared, as follows: 1/2 lb. mushrooms. Salt and pepper. 1 tablespoonful butter.

Rinse off the mushrooms, peel the tops and stems and break into pieces. Place in a stew pan, sprinkle lightly with pepper and salt, and let them stand 1 hour until their juice is drawn out, then add butter and stew the mushrooms in their juice 1/2 hour. Add to above gravy and pour over tenderloin.