Preheat oven to 180°C. Heat oil in a large frying pan over medium heat. Add the Sadia Chicken Drumsticks and cook until golden. Transfer to a large ovenproof casserole dish. Cut the Sadia Chicken Franks into thick slices and add to the frying pan and brown. Transfer to the casserole dish.
Add the onion and garlic to the frying pan and cook, stirring for 5 minutes until softened. Add the celery and mushrooms and cook for a further 2 minutes. Stir in the tomatoes, chicken stock and oregano and bring to a boil. Remove from the heat and pour into the casserole dish. Cover and place in the oven.