Preheat oven to 180°C. Heat oil in a large flameproof casserole dish over a high heat. Add chicken and cook, stirring until brown. Remove chicken from casserole dish
Add chorizo to casserole dish. Cook, stirring for 3 minutes. Remove from casserole dish. Add onion to casserole dish and cook, stirring occasionally for 3 minutes, then add rice and garlic and cook, stirring for 2 minutes longer
Add Napoletana sauce, stock, wine ,pepper, chicken and chorizo and stir to combine. Bring to the boil. Cover and bake 15 minutes. Remove from oven and stir; cover and bake 10 minutes longer.
Remove from oven and stir in peas and capsicum. Cover and bake for 5 minutes longer.
Remove from oven. Stir and cover. Allow to sit for 5 minutes, then stir in chopped parsley and Parmesan. Serve garnished with extra parmesan