1 lb. fresh mushrooms, washed, dried & sliced
1/2 c. butter
1/2 c. chopped bell peppers
1/2 c. chopped onions
1/2 c. chopped celery
1/2 c. mayonnaise
10-12 slices very thin white bread
1/4 c. butter, melted
Salt & pepper to taste
2 eggs
1 1/2 c. milk
1 (10 3/4 oz.) can cream of mushroom soup
1/4 lb. Swiss cheese, grated

Saute mushrooms in 1/2 cup butter for about 5 minutes. Remove from heat and add peppers, onions, celery and mayonnaise. Mix well and set aside. Grease a 9"x13" baking dish. Brush bread very lightly with melted butter and arrange half in butter of baking dish, covering well. Spread mushroom mixture evenly over bread and sprinkle with salt and pepper. Top with remaining bread. Mix eggs and milk, adding a dash of salt. Pour evenly over casserole.

Cover and refrigerate overnight. Before baking, spread with undiluted mushroom soup and sprinkle with grated cheese. Bake at 300 degrees for 1 hour and 15 minutes, until top is brown and puffy. Serves 12.