Cheesy Chicken & Rice Casserole Cream of Mushroom Soup 1 1/3 Cup Water 1 1/4 Cup uncooked long-grain white ice 1/2 tsp onion powder 1/4 tsp ground black pepper 2 cups frozen mixed vegetables 4 Skinless, boneless chicken breast Stir everything but chicken in an 11X18 shallow baking dish. top with chicken and season. Cover. Bake at 375F for 50 minutes or until the chicken is cooked through and rice is tender. let stand for 10 minutes,Stir rice before serving.