Preheat oven to 350 degrees F. Grease a 2-quart casserole dish.
In a large frying pan over medium heat, melt butter or margarine. Add onion and bell pepper and sautuntil tender; stir in flour and then add milk. Cook, stirring constantly, until mixture has thickened and is smooth. Remove from heat; add corn, cheddar cheese, eggs, sugar, salt, and pepper.
Pour into prepared casserole dish and top with bread crumbs.
Set into a shallow pan of hot water and bake 45 minutes. Remove from oven and serve immediately.
Makes 6 servings.
* You could also substitute frozen corn, if desired.
Iowa Corn Au Gratin Recipe: https://whatscookingamerica.net/vegetables/iowacorn.htm