In a large skillet, cook sausage over medium heat until no longer pink; drain. Stir in 2 tablespoons butter, flour, salt and pepper until blended. Gradually add milk. Bring to a boil; cook and stir for 2 minutes or until thickened. Stir in hash browns and eggs. Transfer to a greased 1-qt. baking dish.
Toss cornflakes and remaining butter; sprinkle over sausage mixture. Bake, uncovered, at 350° for 25-30 minutes or until heated through. Sprinkle with onions. Yield: 3 servings.