Preheat your oven to 375°F and line a baking sheet with parchment paper. Clean mushrooms gently with a damp cloth and carefully remove stems, creating deep wells for filling.

Heat 2 tbsp olive oil in a large skillet over medium heat, then sauté diced onion until translucent, approximately 4–5 minutes. Add minced garlic and cook for another minute until fragrant, stirring frequently to prevent burning.

In a large mixing bowl, combine the sautéed garlic mixture with breadcrumbs, Parmesan, cream cheese, eggs, parsley, thyme, oregano, salt, and pepper. Stir until well incorporated and the filling reaches a moist, cohesive consistency suitable for stuffing.

Brush mushroom caps generously with remaining olive oil and melted butter, then arrange gill-side up on the prepared baking sheet. Spoon the filling into each cap, mounding slightly and creating cozy stuffed mushrooms recipe that will bake evenly and retain moisture.

Pour vegetable broth into the bottom of the baking sheet around mushrooms to prevent drying. Bake for 35–40 minutes until mushroom caps are tender and the filling is golden brown and heated through completely.

Remove from oven and let rest for 3 minutes before serving to allow flavors to settle and filling to firm slightly.