Whenever I talk about how much I love doing new recipes, and I'm asked "which one is your favorite?", this is the first one to come to mind. I found it on a recipe card sponsored by my local grocery store. It's a big production in my house, but it's worth our effort! Anyone else, though, can make it less expensively and faster, too, with a few simple tricks. . .
Preheat oven to 375*F. Clean mushrooms and remove stems.
Brush caps with 2 tbsp melted butter and arrange, hollow side up in 13 x 9 baking dish. Season with salt and pepper.
Finely chop mushroom stems; saute with green onion in remaining butter 10 - 12 minutes until most of the liquid is evaporated, stirring frequently. Lower heat and stir in flour, cooking for 1 minute. Add cream and simmer until thickened. Stir in Parmesan and parsley.
Fill mushroom caps with mixture. Top each with 1 tsp swiss cheese. Bake at 375*F for 30 minutes. If taking away, DO NOT COVER WITH ANYTHING THAT FLEXES! It will adhere to the hot cheese and ruin the presentation.
***Note: These mushrooms can be made a day in advance. Prepare and stuff mushrooms; top with cheese. Cover and refrigerate until ready to bake and serve.