Cook the Spaghetti:

Bring a large pot of salted water to a boil. Cook the spaghetti until just al dente, according to package instructions. Drain and set aside.

Sauté the Vegetables:

In a skillet, heat butter or olive oil over medium heat. Add the onion, green bell pepper, and garlic, and sauté until softened, about 3-5 minutes.

Prepare the Sauce:

In a large mixing bowl, combine the cream of chicken soup, cream of mushroom soup, diced tomatoes and green chilies, chicken broth, and 1 cup of shredded cheese. Mix in the garlic powder, onion powder, paprika, salt, and pepper. Stir in the sautéed vegetables.

Combine Ingredients:

Add the cooked spaghetti and shredded chicken to the bowl with the sauce. Toss until the spaghetti and chicken are well coated.

Assemble the Casserole:

Preheat your oven to 350°F (175°C). Grease a 9x13-inch baking dish and pour the chicken spaghetti mixture into the dish. Spread it evenly.

Top with Cheese:

Sprinkle the remaining 1 cup of shredded cheddar cheese evenly over the top.

Bake:

Bake in the preheated oven for 25-30 minutes, or until the cheese is melted and bubbly.

Serve:

Let the casserole cool slightly before serving. Enjoy hot with a side of garlic bread or a crisp green salad.