Cook noodles according to package directions. In the bottom of a deep skillet saute minced onion in oil until transparent. Remove onion and brown ground beef. Drain off any excess fat. Add onion back to pan along with cream of mushroom soup, salt and pepper. Stir. Remove from heat and stir in sour cream. Mix well. Drain noodles, do not rinse and mix with soup mixture. Pour onto serving platter and top with fresh chopped parsley.
You can also pour into buttered casserole dish and sprinkle with bread crumbs and bake at 350 degrees until bubbly.