Boil noodles in water, 3/4 of the box is plenty. Drain, mix with milk and Ricotta. Brown hamburger and drain. Add spaghetti sauce, salt. Grease 9 x 12 inch casserole. Layer beginning with noodles, sauce, cheese, repeat 3 times. Top with Parmesan and bake at 350ºF. for 30-45 minutes. Remove and cool slightly to set.