Grease a 1 1/2- to 2-quart baking dish. Heat the oven to 325°.
Heat 4 tablespoons of butter in a medium saucepan; add onion and saute until tender. Stir in the flour and cook, stirring, for 1 minute. Add the milk. Cook, stirring, until thick. Stir in the Cheez Whiz; stir in the eggs. Fold in the broccoli and turn into the prepared baking dish.
Sprinkle with the corn flakes, dot with butter, and sprinkle with a little paprika.
Bake for 30 minutes.
Calories per serving: 327