Wash mushrooms and remove stems.
Chop stems and set aside.
Place mushrooms hollow side up in baking dish.
Brush with melted butter.
Sprinkle with salt and pepper.
Saute butter, oil, shallots, onions and mushrooms stems.
Remove from heat and add bread crumbs.
Add cheeses, parsley, tarragon, salt and pepper.
Add cream slowly to thicken.
Stuff mushrooms with mixture and sprinkle with swiss cheese and melted butter.
Bake at 375 degrees for 15 to 20 minutes.