1-Step 1: Get the oven and pan ready Preheat the oven to 325°F. Then spray a 9×13-inch casserole dish or glass baking pan with cooking spray. A glass baking pan is especially helpful because it supports more even rice cooking. This small step makes a noticeable difference in the final texture of your chicken rice casserole.

2-Step 2: Season and arrange the chicken Place the 4 boneless skinless chicken breasts in the prepared dish. Season them with salt and pepper to taste. If you are using chicken thighs instead, place them in the same way and keep the seasoning simple so the soup mix can do the heavy lifting.

3-Step 3: Add the rice and onion soup mix Pour 1 cup of uncooked long grain white rice over the chicken. Sprinkle the 1 ounce dry onion soup mix evenly across the top. Make sure the rice is spread out as evenly as possible so it cooks at the same pace. If you want a little more flavor later, you can stir in onions or mushrooms before baking.

4-Step 4: Mix the creamy sauce In a separate bowl, combine the 10.5 ounces condensed cream of mushroom soup with 1.5 cups water. Stir until smooth. This mixture forms the creamy base that gives the casserole its soft, comforting texture. It also helps the rice cook properly while keeping the chicken moist.

5-Step 5: Pour and cover Pour the soup mixture evenly over the chicken and rice. Try to cover as much of the rice as possible so it can soak up the liquid during baking. Then cover the dish tightly with a lid or foil. Good coverage matters because it traps steam, which helps the rice become tender.

6-Step 6: Bake until tender Bake the casserole for 1 hour 15 minutes at 325°F. When the time is up, check the rice for tenderness. If the rice still feels firm, keep baking for up to an additional 25 minutes. Every oven behaves a little differently, so this extra time can be useful. The chicken should be cooked through and the rice should be soft and fluffy.

7-Step 7: Rest and serve Let the casserole rest for a few minutes before serving. This helps the sauce settle and makes it easier to scoop onto plates. Serve warm and enjoy the creamy chicken, tender rice, and savory flavor in every bite.