2 pkg. frozen French cut green beans, cooked and drained
2 tbsp. butter
1/4 c. minced onions
2 tbsp. flour
1 tsp. salt
1/4 tsp. pepper
1/4 tsp. dry mustard
3/4 tsp. Worcestershire sauce
1 c. sour cream or plain yogurt

Heat butter. Add onion and cook over medium heat until tender. Remove from fire and blend in dry ingredients which have been mixed together. Remove and cool slightly. Add sour cream and cook over low heat, stirring constantly, until thickened (2 to 3 minutes). Pour over green beans in a casserole. Sprinkle with grated cheese and heat in 350 degree oven until cheese is melted.