1 1/2 lb. fresh green beans (or use frozen)
1/4 c. (1/8 lb.) butter
1/4 c. chopped onion
1/2 lb. mushrooms, sliced
3 tbsp. flour
1 tsp. salt
1/8 tsp. each pepper, thyme, marjoram
1 c. milk
1 c. shredded Swiss cheese (about 4 oz.)
1/3 c. sherry or additional milk

Cook beans until tender; drain and set aside. Heat butter in pan and saute onions and mushrooms until tender, about 6 minutes. Stir in flour, salt, pepper, thyme and marjoram. Gradually stir in milk. Bring to boiling, stirring and cook until thickened. Remove from heat and add 1/2 cup cheese, the additional liquid and beans. Mix together and pour into 1 1/2 quart casserole. Sprinkle with remaining cheese. Bake uncovered at 400 degrees until heated through, about 30 minutes.