Wash chicken breasts, pat dry, and remove excess fat. Heat roughly 1 tablespoon oil in a large pan over medium-high heat. Sear chicken for 3 minutes per side until golden brown (it will continue cooking in the oven).
Cut one tomato into eighths. Wash and deseed the yellow bell pepper, then cut into small pieces. Slice the spring onions into rings. Spread vegetables in a baking dish, season with salt and pepper. Place seared chicken on top.
Cut the second tomato into small pieces. Fry in the same pan over medium heat for 2 minutes. Scatter the fried tomato pieces over the chicken. Spread mozzarella evenly over top.
Pour the cremefine into the same pan and add the tomato paste, stirring to combine. Season with salt and pepper. Simmer over medium heat for 5 minutes. Pour this sauce over the chicken and vegetables in the baking dish.
Preheat oven to 180°C (356°F). Bake for 15-20 minutes until chicken reaches an internal temperature of 74°C (165°F). Serve with cooked rice and ciabatta.