Preheat oven to 375°F (190°C).
Clean mushrooms with a damp cloth, remove stems, and set caps aside. Finely chop the stems.
In a bowl, combine cream cheese, Parmesan, minced garlic, chopped mushroom stems, and parsley. Season with salt and pepper.
Spoon or pipe the filling evenly into each mushroom cap.
Mix melted butter with breadcrumbs, then sprinkle the mixture over the filled mushrooms.
Arrange mushrooms on a baking sheet and bake for 15–20 minutes, until tops are golden brown and filling is bubbly.
Remove from oven, let cool slightly, then serve warm.
