Remove stems from mushroom caps and chop.
Wash caps, dry and dip in lemon juice, mixed with 1/4 teaspoon salt and pepper.
Place caps in buttered shallow casserole.
Saute chopped mushrooms in 1/4 cup butter for 2 to 3 minutes.
Stir in flour and let bubble.
Gradually add milk and cook and stir until mixture boils and is thickened.
Add 1/2 teaspoon salt, pepper and 1/3 cup of cheese.
Cover and keep warm.
To make dumplings: Bring 1/2 cup butter and water to a boil, add 1 cup flour and stir over low heat until mixture leaves sides of pan.
Remove from heat.
Add eggs, one at a time, beating after each addition until mixture is smooth and glossy.
Stir in 1/4 cup of the cheese.
Drop by rounded tea-spoonfuls into boiling salted water and cook until dumplings rise to the top, 2 to 3 minutes.
Drain.
Place dumplings on mushrooms in casserole.
Cover with cheese sauce and sprinkle with remaining cheese.
Bake in a 375° F.oven 20 to 25 minutes or until cheese is lightly browned.