Spray the bottom of a casserole dish about 5 times with the cooking spray, place over a high heat, and then once the oil starts to bubble turn the heat down a little, add the sliced onion and sauté for about 4 minutes.
Add the carrots and continue to cook everything for a further 2 – 3 minutes.
Stir in the dried thyme and cook for a further minute.
Add the tin of tomatoes, sweetcorn and peas and combine everything together well.
Add the chicken stock and corn flour paste. Bring everything to the boil and then turn down allowing to simmer for about 5 minutes.
Add the chicken and allow to cook for about 15 – 20 minutes. Check the chicken is cooked by cutting a piece in half, to check it’s not still pink inside.
Season to taste.
Serve with a little whole grain rice or a few new baby potatoes.