Preheat oven to 350°F.
In a large bowl, mix cream of chicken soup and milk (or water) until smooth.
Stir in cooked rice.
Fold in drained chicken and peas & carrots.
Spread evenly into a greased 9x13 baking dish.
Cover tightly with foil.
Bake 20-25 minutes until heated through.
Remove foil, add shredded cheese if using, and bake uncovered 5-10 minutes until melted and bubbly. Let rest 5 minutes before serving.