Preheat oven to 375 degrees F.
In a medium bowl stir cream cheese, sour cream, and mayonnaise until mostly smooth.
Add spinach, artichokes, garlic, 1/2 cup mozzarella cheese, white cheddar, Parmesan cheese, salt, pepper, red pepper flakes, and hot sauce and stir until well combined.
Transfer mixture to a medium baking dish and sprinkle remaining 1/4 cup mozzarella on top.
Bake for 25-30 minutes, or until cheese is melted and slightly browned on top.
Sprinkle with additional chili flakes if desired, and serve warm with bread, chips, veggies, or anything else your heart desires!