Preparing Creamy Chicken Casserole is straightforward if you follow these simple steps:

1. Preheat Oven: Preheat your oven to 350°F (175°C).
2. Sauté Vegetables: In a skillet over medium heat, add olive oil. Sauté frozen mixed vegetables until heated through, about 5-7 minutes.
3. Combine Sauce Ingredients: In a large mixing bowl, combine the cream of chicken soup, sour cream, garlic powder, onion powder, thyme, salt, and pepper. Mix until smooth.
4. Add Chicken and Vegetables: Stir in the shredded chicken and sautéed vegetables. Ensure everything is well coated in the creamy mixture.
5. Transfer to Casserole Dish: Pour the chicken mixture into a greased 9×13-inch casserole dish, spreading it evenly.
6. Add Cheese: Sprinkle shredded cheddar cheese over the top of the chicken mixture.
7. Cracker Topping: Evenly distribute the crushed crackers over the cheese to create a crunchy topping.
8. Bake: Place the casserole in the preheated oven and bake for 40-45 minutes, or until the edges are bubbly and the top is golden brown.
9. Rest: Once baked, remove from the oven and let the casserole rest for 5-10 minutes before serving.
10. Garnish: Optionally, sprinkle with chopped fresh parsley for a pop of color.

By following these steps, you can easily create a delectable Creamy Chicken Casserole that your loved ones will rave about!