Heat olive oil in a large oven-safe pot or skillet and add chicken. Season with salt, pepper, Italian seasoning and garlic powder then cook for 6-8 minutes, until the outside is no longer pink.
Stir in marinara sauce, water and uncooked ziti and bring to a boil. Cover and cook for 10-15 minutes, stirring occasionally, until pasta is tender. Stir in parmesan cheese and 1/2 cup mozzarella cheese until melted.
Remove from heat, spread pasta in an even layer in the skillet and sprinkle remaining mozzarella on top. In a small bowl, combine melted butter and breadcrumbs and sprinkle on top.
Transfer pan to the oven and broil for 1-2 minutes until breadcrumbs are toasted. Garnish with fresh parsley before serving.