1. Heat oven to 350 degrees. 2. In large mixing bowl, combine all casserole ingredients. Beat until light and fluffy. 3. Place in 8 x 8 x 2 inch pan. For Topping: 4. Cream together butter, flour and sugar. 5. Stir in pecans. 6. Spread mixture evenly over top of potato mixture 7. Bake for approx. 50 minutes. Serve hot.