Preheat oven to 400°F (200°C) and line a baking sheet with parchment paper.
In a medium bowl, mix the ground chicken, Parmesan cheese, egg, garlic powder, oregano, salt, and black pepper until well combined.
Place the chicken mixture onto the parchment paper and flatten into a circular or rectangular shape approximately 1/4 inch thick.
Bake the crust for 20 minutes or until the edges are golden brown and the center is cooked through.
Remove from the oven and spread the marinara sauce evenly over the crust.
Top with shredded mozzarella cheese and pepperoni slices.
Return to the oven and bake for an additional 10 minutes until the cheese is melted and bubbly.
Let the pizza rest for 5 minutes before slicing to allow the crust to set.