Put the chicken in a flameproof casserole with the butter, oil and onion and cook over a medium heat, stirring and turning frequently, for about 15 minutes until browned. Add the tomatoes, carrot and celery, pour in 150 ml / 1/4 pint water, cover and simmer for 45 minutes until the chicken is tender and cooked through. Sprinkle in the parsley and season with salt and pepper. This is the simples way to prepare chicken cacciatore - in some regions more celery and carrots are added, in others white wine is used instead of water or stock, and in still others sliced mushrooms are added.
Coll. (2010), "The Silver Spoon", Phaidon, 922