Begin by boiling a large pot of water over high heat. Add the spaghetti and cook according to package instructions, typically around 8-10 minutes until al dente. Stir occasionally to prevent sticking. Once done, drain the pasta in a colander and set aside.

In a large skillet, heat one tablespoon of olive oil over medium heat. Add the chopped onion, bell pepper, and sliced mushrooms to the skillet and sauté for 5-7 minutes until the vegetables become soft and slightly browned.

Reduce the heat to low and stir in one can of cream of chicken soup along with one cup of sour cream. Add half a teaspoon of garlic powder and onion powder, mixing well for about 2-3 minutes until the sauce is smooth and creamy.

Fold in the cooked, shredded chicken and half a cup of shredded Monterey Jack cheese into the sauce. Stir continuously until the cheese is completely melted.

Gently add the drained spaghetti into the skillet, tossing everything together until the pasta is evenly coated with the creamy sauce. Continue to cook for an additional 2-3 minutes.

If you prefer a baked version, preheat your oven to 350°F (175°C). Transfer the spaghetti mixture into a greased baking dish. Top with the remaining Monterey Jack and cheddar cheese, then bake for 20-25 minutes.

Remove from the oven and let it cool for a few minutes. Garnish the dish with freshly chopped parsley for a pop of color and freshness.