Preheat oven to 350°. Combine 1 1/2 cups mozzarella, sour cream, 2 tablespoons Parmesan, and next 6 ingredients (through spinach) in a large bowl; stir until well blended. Spoon mixture into a 1 1/2-quart baking dish. Sprinkle with remaining 1/2 cup mozzarella and remaining 2 tablespoons Parmesan. Bake at 350° for 30 minutes or until bubbly and golden brown. Serve with tortilla chips.
Loved it! Used the entire pkg of spinach and added a dash of cayenne. Sometimes I use two reduced-fat cream cheese blocks, instead of one fat-free. We like it better with crostini or pita chips instead of tortilla chips.