-Sour cream Cook noodles as directed on package. Drain. Line bottom of 9 inchx13 inch pan with noodles. In medium bowl, mix cottage cheese, egg and onion salt together. Spread over noodles. Cover with a layer of noodles. In same bowl, mix cheddar cheese with potatoes, salt, onion salt and pepper. Spread over noodles. Cover with another layer of noodles. Melt butter in pan. Saute onion until transparent and soft. Pour over noodles. Cover. Bake 30 minutes in 350 degree oven. Let stand 10 minutes before serving. Serve with sour cream.