Preheat your oven to 425°F (220°C) and line a baking sheet with parchment paper.
In a large mixing bowl, combine the shredded chicken, 1 cup of mozzarella cheese, Parmesan cheese, egg, garlic powder, Italian seasoning, salt, and black pepper. Mix until well combined.
Transfer the chicken mixture onto the prepared baking sheet and shape it into a round pizza crust, about 1/2 inch thick.
Bake the crust in the preheated oven for 15-20 minutes, or until it is golden brown and firm to the touch.
Remove the crust from the oven and spread the pizza sauce evenly over the top. Sprinkle with the additional mozzarella cheese and your desired toppings.
Return the pizza to the oven and bake for an additional 10-15 minutes, or until the cheese is melted and bubbly.
Let the pizza cool for a few minutes before slicing and serving.