Preheat oven to 190°C.
Dice the chicken, onion and peppers.
Add everything except the mozzarella into a large ovenproof dish.
Rinse the tomato tin with 100ml water and pour in.
Mix thoroughly.
Top with the mozzarella, cover with foil and bake for 45 minutes.
Remove foil for the final 5 minutes.
Leave to rest for 5-10 minutes before serving.
