Boil onion chunks for 15 to 20 minutes; drain and rinse.
Melt butter in a saucepan. Stir in flour, broth and milk, stirring constantly until thickened. Add onions, salt and pepper. Place onion mixture in a 1 1/2-quart casserole dish, top with cheese and cracker crumbs, then dot with butter. Bake at 375 degrees F for 30 minutes.Makes 4 to 6 Source: