Heat oven to 350 degrees. Cook beef and onion in skillet until brown; drain. Spoon into an ungreased 13x9x2-inch baking dish. Stir in taco seasoning mix (dry), tomato sauce and corn. Sprinkle with cheese. Stir remaining ingredients until blended. Pour over beef mixture. Bake 35 minutes or until light brown. Serve with sour cream, chopped tomato and shredded lettuce, if desired. 8-10 servings. NOTE: At high altitudes, heat oven to 375 degrees. From a collection of my mothers (Judy Hosey) recipe box which contained lots of her favorite recipes, clippings, etc. Downloaded from Glens MM Recipe Archive, G Internet.