Preheat oven to 350 degrees. Spray a small (1 quart) baking dish with non-stick cooking spray.
In a mixing bowl stir together cream cheese, sour cream, mayonnaise, garlic, parmesan, mozzarella and pepper.
Stir in artichokes and spinach.
Spread mixture evenly into prepared baking dish. Bake in preheated oven until heated through and melty, about 20 minutes.
Serve warm with tortilla chips, crackers or toasted baguette slices