Use a good quality bread not that store-bought sandwich white bread. Fry bread in butter until golden or toast bread and then butter. Cook garlic in microwave with onion on high power for 1 minute. Add mushrooms and cook 2 minutes on high stirring after 1 minute.
Add juice from 2 lemons, parsley, wine and salt and pepper. Cook 2 more minutes on high. Stir and cover and let set 3 minutes. Mushrooms should appear wilted, Serve mushrooms over the toast with some of the liquid. You can add more garlic to taste.