Preheat oven to 400°F (200°C). Line a baking tray with parchment paper and place mushroom caps evenly onto tray; set aside.
In a large bowl mix Green Giant* canned corn, cream cheese, mozzarella, garlic, basil, 2 tbsp. of parsley and 2 tbsp. of parmesan cheese until combined. Season with salt and pepper. Fill each mushroom cap with filling.
In a small bowl mix breadcrumbs, 2 tbsp. of parmesan cheese and butter together. Generously sprinkle each mushroom. Cook for 15 minutes until tops are golden brown.
Transfer to a serving tray and sprinkle with remaining chopped parsley. Serve warm and enjoy.