Preheat your oven to 350 degrees F (175 degrees C).
Heat the olive oil in a large skillet over medium heat.
Quarter the white mushrooms and add them to the skillet. Season with salt and pepper to taste. Sauté the mushrooms until they have softened and most of the water has cooked off, which takes about 7-9 minutes.
Add the minced garlic to the skillet and cook until fragrant, approximately 1 minute.
Stir in the cubed cream cheese until the mushrooms are evenly coated.
Remove the skillet from heat and mix in the mozzarella, ½ cup of bread crumbs, and ¼ cup of Parmesan.
Once combined, transfer the mixture to a greased 8x8 baking dish.
In a small bowl, combine the chopped parsley, melted butter, remaining Parmesan, and bread crumbs. Sprinkle this mixture on top of the mushrooms in the baking dish.
Bake in the preheated oven for 25-30 minutes, or until the breadcrumb topping turns golden and crispy.
Remove from the oven and let it cool slightly before serving. Enjoy!