Preheat the oven to 375° F.

Steam the spinach until it is wilted and then squeeze out as much water as you can, then dab with a paper towel if need be. Shred your spinach with a knife or scissors.

In a bowl, mix cream cheese, sour cream, baby spinach, garlic, salt, pepper, half the Parmesan cheese, and half the mozzarella cheese together. 

Pour the mixture into an oven safe dish, then sprinkle the rest of the mozzarella and Parmesan on top. Pop it into the oven, and bake for 20 – 25 minutes, or until the cheese is all melted and the top is a little bubbled and browned.