Pat the chicken dry with a paper towel, then season and place, skin-side down, in the pan. Heat oil in a large, deep frypan over medium heat. Cook for 4 minutes or until skin is golden, then turn and cook for a further 1 minute or until browned. Transfer to a plate.
Place the pan back on medium heat, add the onion, and cook, stirring, for about 2 minutes or until softened. Stir in the garlic and rosemary, cooking for an additional minute until fragrant.
Add the capsicum, olives, and red wine, and let it cook for 3-4 minutes, allowing the liquid to reduce by half. Mix in the tomato, and chicken stock.
Return the chicken, skin-side up, to the pan. Bring the mixture to a simmer and cook for 12 minutes, or until the chicken is thoroughly cooked.
Garnish with parsley and serve with polenta, if desired