3 (10 oz.) pkgs. string beans, frozen
2 tbsp. butter
2 tbsp. flour
1 tsp. salt
1/4 tsp. pepper
1 tbsp. sugar
1 tsp. onion
1 pt. sour cream
1/2 lb. Swiss cheese
1/2 c. bread crumbs or Captain Wafers
1 tbsp. melted butter

Cook beans according to package and drain. Combine melted butter, 2 tablespoons flour, salt, pepper, sugar, onion, and sour cream; cook until blended. Combine with beans and put in casserole. Cover with cheese. Combine bread crumbs with 1 tablespoon butter and sprinkle over cheese. Bake for 20 minutes at 400 degrees.