Prepare the chicken by shredding it into bite-sized pieces. If using raw chicken, boil or bake until fully cooked, then shred.
In a large mixing bowl, combine shredded chicken, mozzarella cheese, cheddar cheese, ranch dressing, crumbled bacon, and chopped green onions. Add garlic powder, onion powder, paprika, and black pepper. Mix until well combined.
Roll out the pizza dough on a floured surface to a rectangle shape, about 1/4 inch thick. Spoon the chicken mixture down the center, leaving 1 inch of space on each side. Fold the sides over the filling and pinch to seal.
Preheat oven to 400°F. Line a baking sheet with parchment paper. Place the filled dough seam-side down on the baking sheet. Bake for 20-25 minutes until golden brown. Let cool for a few minutes before slicing.