Heat a large pan over medium high heat. Season both sides of the chicken breasts with salt and pepper. Add the olive oil into the pan. Then add in the chicken. Cook for about 2 minutes on each side until browned. The chicken does not have to be fully cooked. Remove it from the pan and set aside.
Decrease the heat to medium. Add in the butter and allow it to melt. Mix in the onion, carrots, and celery. Sauté the vegetables for 5-7 minutes util slightly softened. Mix in the garlic and cook for another minute. Add in the chicken broth, poultry seasoning, and pasta. Mix until combined. Nestle the chicken breasts back into the pan. Bring the broth to a bubble then reduce the heat to medium low so that it is gently simmering. Cover the pan with a lid and cook for 15-18 minutes until the pasta is al dente.
Remove the chicken from the pan and set it aside to cool for a few minutes. Mix the heavy cream, parsley, kosher salt, and black pepper into the pasta. Dice the chicken into small pieces then add it back into the pan. Mix the chicken with the pasta until evenly combined. Taste for seasoning and adjust if necessary. Enjoy!