1. Bring a large pot of salted water to a boil. Add the spaghetti and cook until al dente. Reserve ¾ cup of the pasta water, then drain and set aside.

2. Pat the chicken dry and season with garlic powder, onion powder, Italian seasoning, smoked paprika, salt, and pepper.

3. Heat olive oil in a large skillet over medium-high heat. Add chicken in a single layer and sear for 4–5 minutes, flipping halfway, until golden and cooked through. Remove and set aside.

4. In the same skillet, reduce heat to medium and add butter. Sauté onion for 2–3 minutes until translucent, then stir in garlic and cook another 30 seconds.

5. Deglaze the skillet with chicken broth or pasta water, scraping up brown bits. Let simmer for 2–3 minutes.

6. Stir in heavy cream and bring to a gentle simmer to thicken slightly.

7. Reduce heat to low. Stir in Monterey Jack cheese and Parmesan until fully melted and smooth. Add red pepper flakes if using.

8. Add cooked spaghetti and seared chicken into the sauce. Toss to combine, using extra pasta water if needed to loosen the sauce.

9. Remove from heat and garnish with fresh parsley, extra cheese, and a squeeze of lemon if desired. Serve hot.