Onion Sauce

Parboil 4 or 5 onions in water. Drain. Cover with milk. Let them boil gently one-half hour. Turn off the milk. Chop the onions fine. Put 1 tablespoonful of butter into the saucepan. Stir in 1 teaspoonful of flour smoothly. Add the milk by degrees. Stir until it thickens. Add the onions and let it boil up.