Preheat a large skillet to medium heat with a drizzle of olive oil. Add the chicken and sprinkle with salt and pepper. Cook for about 6 minutes on each side until browned and cooked through. Remove to a plate to let cool. When the chicken is cool enough to handle, shred into bite-sized pieces, reserving any juice that collects on the plate.

When the chicken is out of the pan, add the peppers to the same skillet with another drizzle of oil. Cook for 2 minutes until browned but not soft, then add the garlic. Stir, and cook for 1 minute.

Add the cooked spaghetti, Alfredo sauce, shredded chicken, and ½ the tomatoes to the skillet with a splash of the cooking water. Toss everything together gently with tongs, adding more cooking water as needed to coat the pasta with the sauce. Taste, and add more salt and pepper if needed.

Serve the pasta topped with the remaining tomatoes and a sprinkle of parmesan. Enjoy!