Preheat your oven to 200°C (390°F). Gently clean the mushroom caps with a damp cloth, then set them aside to dry. Carefully remove the stems and chop them finely, setting aside a few for stuffing later.
Brush the mushroom caps lightly with olive oil, coating all over, then place them gill-side up on a parchment-lined baking tray. Bake for 8-10 minutes until they begin to soften and smell earthy and fragrant.
While the caps bake, combine the cream cheese, grated Parmesan, chopped mushroom stems, minced garlic, chopped parsley, thyme, lemon juice, and a pinch of salt and pepper in a mixing bowl. Stir until the mixture is smooth and well combined.
Remove the mushroom caps from the oven and carefully spoon the filling into each, pressing gently to pack it in. Return the tray to the oven and bake for another 12-15 minutes, until the filling is golden and bubbling around the edges.
Once baked, transfer the mushroom caps to a serving platter and let rest for 3-5 minutes. The filling will set slightly and the aroma of herbs and cheese will be irresistible.
Garnish with extra chopped parsley or a drizzle of olive oil if desired, then serve warm for a perfect bite-sized appetizer or light main.
