Preheat oven to 375 degrees and spray a 13x9“ casserole dish with non-stick spray.
In a large bowl, combine alfredo sauce, cream cheese, and sour cream. Stir until smooth.
Now add the chopped (drained) spinach, minced garlic, chopped artichoke hearts, 3/4 cup of the grated parmesan, 1 cup of the shredded mozzarella, salt, and pepper. Stir well to combine.
Pour spinach mixture into the prepared casserole dish and top with the remaining 1/4 cup of grated parmesan and 1/2 cup mozzarella.
Bake for 30 minutes or until the cheese is melted and the dip is bubbly and slightly browning on top.
Serve right away while hot. Enjoy!