Prep Mushroom Caps: Preheat oven to 400°F (200°C). Wipe mushrooms clean with a damp paper towel. Pop out stems and finely mince them. Arrange caps hollow-side up on a parchment-lined baking sheet and brush lightly with olive oil.

Sauté Stems & Garlic: Melt 2 tablespoons butter in a skillet over medium heat. Add minced mushroom stems and shallots. Sauté for 4 to 5 minutes until tender and moisture evaporates. Stir in minced garlic and cook for 1 minute until fragrant. Remove from heat and cool slightly.

Mix Cream Cheese Filling: In a medium bowl, beat softened cream cheese until smooth. Fold in the sautéed garlic-stem mixture, grated Parmesan, fresh parsley, chives, thyme, onion powder, salt, and black pepper until completely blended.

Stuff Caps: Generously spoon or pipe the garlic herb cream cheese filling into each mushroom cap, mounding it slightly in the center.

Crisp Panko Topping: In a small ramekin, toss panko breadcrumbs with 1 tablespoon melted butter and 2 tablespoons extra Parmesan. Sprinkle over the top of each stuffed mushroom.

Bake & Garnish: Bake at 400°F (200°C) for 18 to 22 minutes until mushrooms are tender and juicy, and the panko topping is deeply golden brown and crunchy. Garnish with fresh parsley and serve warm!