1. Preheat oven to 375 degrees F. Coat a rimmed baking pan with cooking spray; set aside. Wipe mushrooms clean with paper towels; remove stems and discard. Brush inside and outside with olive oil.
2. In a medium bowl, combine stuffing mix and the boiling water. Cover and let stand for 5 minutes or until slightly softened. Stir in ricotta, mozzarella, 2 tablespoons of Parmesan cheese, pesto and garlic. Spoon stuffing mixture into mushroom caps. Place caps on prepared baking sheet. Sprinkle with remaining 2 tablespoons Parmesan cheese. Bake for 20 to 25 minutes or until golden brown.
Excerpted from the book, Sandra Lee Semi-Homemade Cocktail Time, by Sandra Lee Copyright 2009 SLSH Enterprises, Inc.