2 x 125g packs reduced fat mozzarella, sliced and drained on kitchen paper
Season the chicken breasts with salt and pepper. Spray a large, deep non-stick flameproof frying pan or sauté pan with oil and place over a high heat. Cook the chicken on each side for 3 minutes or until lightly browned. Transfer to a plate.
Reduce the heat to low, spray a little more cooking oil into the pan and cook the vegetables for 4-5 minutes, stirring until softened. Add the garlic infused oil and cook for a few seconds.
Pour in the tomatoes. Stir in the tomato purée, oregano and olives. Bring to the boil and cook for 5 minutes, stirring regularly.
Reduce the heat to a gentle simmer and add the chicken. Cook for 10 minutes, stirring occasionally, until the chicken is tender and cooked through. Season to taste.
Preheat the grill to its hottest setting. Top the chicken and sauce with the sliced mozzarella. Sprinkle with ground black pepper. Place under the hot grill and cook for 2-3 minutes or until the cheese melts.