Preheat the oven to 180C/Gas4; heat the oil in a frying pan and fry the onion with a pinch of salt until very soft but not golden, about 15 minutes; add the garlic and rosemary and fry for another minute before stirring in the tomato puree and then the red wine; cook for a few minutes then add the passata and bring to a simmer
transfer to an oven proof dish and stir in the cannellini beans and chicken stock; push the chicken breasts down in the sauce cover with foil and cook in the preheated oven for 2 hours
4 servings