Add cream cheese, mozzarella cheese, grated parmesan, artichoke hearts, garlic, salt, and pepper to a medium saucepan. Cook over medium-low heat until cheese is slightly melted, stirring occasionally, about 6 to 8 minutes.
Add baby spinach to the saucepan (in batches, if needed) and cover. Cook until spinach is wilted, about 3 to 5 minutes, then stir to combine. Continue adding spinach in batches, covering to cook and then stirring to incorporate.
Once all the spinach has been incorporated, stir well and serve hot with pita chips, bread, crostini, or fresh veggies for dipping. Enjoy!