In a large saucepan, heat 2 tablespoons of oil over medium-high heat. Season the chicken breasts or thighs with cajun seasoning, then add them to the pan. Sear the chicken for about 4 minutes per side until golden brown and cooked through. Once done, transfer the chicken to a plate and let it rest for a few minutes.

In the same saucepan, reduce the heat to medium and melt 2 tablespoons of butter. Add diced onion, celery, and bell pepper to the pan, sautéing them for about 5-7 minutes until they become tender and fragrant. Stir occasionally to ensure even cooking and prevent browning.

Next, add 3 cloves of minced garlic, 1 teaspoon of fresh thyme, and an additional teaspoon of cajun seasoning to the sautéed vegetables. Cook for about 1 minute until the garlic is fragrant, stirring continuously to avoid burning.

Pour in 6 cups of chicken broth, stir in the seared chicken (chopped or shredded), and optional diced tomatoes. Add 2 tablespoons of Worcestershire sauce and 2 cups of your chosen pasta. Bring the mixture to a boil, then reduce the heat and let it simmer for about 7 minutes, or until the pasta is al dente.

Once the pasta is cooked, remove the chicken from the soup, shred it, and return it to the pot. Turn off the heat, then stir in 1 cup of heavy cream and 1 cup of grated parmesan cheese, mixing until melted and creamy.

Finally, add a splash of lemon juice, along with chopped parsley and sliced green onions, for a fresh finish. Taste and adjust the seasoning with cayenne, salt, and pepper as desired.