Preheat oven to 400°F and grease a sheet pan with nonstick spray.
In a large bowl combine the cream cheese, mayonnaise, sour cream, garlic powder, salt and pepper. Add artichoke hearts, spinach and Parmesan cheese and stir until combined.
Add spoonfuls of spinach artichoke mixture to the mushrooms, about 1-3 tablespoons per mushroom depending on the size of the mushroom. Place on prepared pan and top with more Parmesan cheese.
Bake until cheese is melted and topping is lightly browned, about 15-20 minutes.
Serve immediately.
NOTES:
- Make ahead: The filling can be mixed up to 5 days in advance and stored in the fridge. The assembled mushrooms can be assembled up to 24 hours in advance and chilled in the fridge until ready to bake. Baked mushrooms can be stored in the fridge for up to 3 days and reheated before serving.
- To reheat: Cover mushrooms with foil and warm in a 350°F oven for about 15 minutes.
Recipe adapted from Taste of Home.
Calories: 75kcal, Carbohydrates: 2g, Protein: 2g, Fat: 7g, Saturated Fat: 2g, Cholesterol: 9mg, Sodium: 200mg, Potassium: 136mg, Fiber: 1g, Sugar: 1g, Vitamin A: 1332IU, Vitamin C: 3mg, Calcium: 45mg, Iron: 1mg