1. Preheat oven to 350F. Spray a 2 quart baking dish with nonstick spray.
2. In a large bowl, combine the potatoes, milk, sour cream, cheese and 2 tablespoons of the melted margarine. Stir gently until well combined. Spread evenly into prepared dish.
3. In a small bowl, combine the crushed cornflakes and remaining 2 tablespoons margarine; sprinkle evenly over potato mixture. Bake, uncovered, until bubbling and lightly browned, about 50 minutes. Serving: (about 1 cup) provides 1 fat, 1/2 protein, 1 Bread, 30 calories. Per serving: 197 calories, 8 gm protein; 23 gm carbo; 8 gm fat; 253 mg sodium; 12 mg chol; 0 gm fiber.