Boil the spaghetti in a large pot of salted water until al dente. Drain and set aside.
Heat olive oil in a large skillet over medium heat. Add the onion and green bell pepper, sautéing until softened, about 5 minutes.
In a large bowl, combine the cream of chicken soup, cream of mushroom soup, chicken broth, garlic powder, salt, pepper, and paprika. Stir until smooth.
Add the cooked chicken, sautéed vegetables, and cooked spaghetti to the sauce mixture. Mix well to coat evenly.
Preheat the oven to 350°F (175°C). Transfer the mixture to a 9x13-inch baking dish and spread evenly. Sprinkle shredded cheddar cheese over the top.
Bake in the preheated oven for 20 minutes or until the cheese is melted and bubbly.
Remove from the oven and let rest for 5 minutes before serving. Enjoy!