01 - Preheat the oven to 375°F. Line a baking sheet with parchment paper.
02 - Clean the mushrooms, remove the stems, and gently hollow out the centers if needed to create more space for the filling. Set mushroom caps aside.
03 - Heat olive oil in a skillet over medium heat. Add minced garlic and sauté for 30 seconds until fragrant.
04 - Add chopped spinach to the skillet and cook until just wilted, about 2 minutes. Stir in chopped artichoke hearts and cook for 1 additional minute. Remove from heat and let cool slightly.
05 - In a mixing bowl, combine cream cheese, sour cream, grated Parmesan, shredded mozzarella, salt, black pepper, and red pepper flakes. Mix until fully incorporated and creamy.
06 - Fold the cooked spinach and artichoke mixture into the cheese base until well combined.
07 - Spoon the filling evenly into each mushroom cap, mounding slightly. Arrange stuffed mushrooms on the prepared baking sheet.
08 - Sprinkle the tops of each stuffed mushroom with the remaining mozzarella and Parmesan cheese.
09 - Bake for 20 to 25 minutes, until the mushrooms are tender and the cheese topping is golden brown and bubbly.
10 - Remove from oven and sprinkle with fresh chopped parsley immediately before serving. Serve warm for best texture and flavor.