Creating the Irresistible Spicy Southern Chicken Spaghetti Casserole is straightforward if you follow these easy steps:

1. Preheat the Oven: Begin by preheating your oven to 350°F (175°C). This ensures that your casserole will bake evenly.
2. Sauté Vegetables: In a large skillet, heat the olive oil over medium heat. Add the chopped onion and bell pepper, sautéing until softened, about 5-7 minutes.
3. Mix Ingredients: In a large bowl, combine the cooked spaghetti, shredded chicken, cream of chicken soup, sour cream, sautéed vegetables, diced tomatoes, and spices. Stir until everything is well mixed.
4. Add Cheese: Fold in ¾ cup of the shredded cheddar cheese, reserving the rest for topping.
5. Transfer to Casserole Dish: Pour the mixture into a greased 9×13-inch casserole dish, spreading it evenly.
6. Top with Cheese: Sprinkle the remaining cheddar cheese evenly over the top of the casserole. If desired, you can also sprinkle breadcrumbs for added texture.
7. Bake: Place the casserole in the preheated oven and bake for 30-35 minutes, or until the cheese is bubbly and golden.
8. Cool Slightly: Once baked, remove from the oven and allow it to cool for about 5 minutes. This will make serving easier.
9. Serve Warm: Grab a spatula and serve generous portions to your family or guests!

With these steps, you’ll bring together a mouth-watering casserole that encapsulates the essence of Southern flavors while being easy to prepare.