In a skillet, heat a drizzle of olive oil over medium heat, add minced garlic, and cook gently until fragrant and lightly golden, about 1 minute.

Add fresh spinach to the skillet, stir until just wilted with vibrant green color, then remove from heat and transfer to a mixing bowl to cool slightly.

In the bowl, combine softened cream cheese and grated Parmesan with the cooled spinach, stirring until smooth, creamy, and well combined.

Adjust rack to center position and heat oven to 375°F (190°C), then line a baking sheet with parchment or foil for easy cleanup.

Using a pastry brush, coat each mushroom cap with olive oil on the exterior and inside gills for a glossy, flavorful base before stuffing.

Spoon the cheesy spinach mixture into each mushroom, mounding generously to create a lovely dome.

Place the tray in the oven and roast for 15–18 minutes, or until cheese is bubbly and edges turn golden brown.

Sprinkle chopped parsley and a pinch of red pepper flakes over hot caps before serving warm.