Preheat oven to 350 degrees F.
Squeeze all excess liquid from spinach, place in a food processor with sour cream, Parmesan, 1/2 cup of the mozzarella, the cream cheese, garlic, pepper and hot sauce.
Process until just blended but still slightly lumpy. Add artichokes and pulse to form a chunky mixture. Place in a 1-quart baking dish. Top with remaining mozzarella. Bake until bubbly, about 30 minutes. Serve with carrot sticks, celery sticks or baked tortilla strips.