Salt chicken, then season with Italian seasoning. You may salt and pepper only, if desired.
In a plate, mix flour, Italian seasoning, and garlic powder. Coat the chicken breast in this flour mixture. Remove the excess flour.
Heat oil in a large sauce-pan or large skillet over medium heat until hot, and then add the chicken. Brown about 4-5 minutes on each side to ensure even brownness. Gently remove chicken and set aside.
Add butter to the same skillet over medium heat until melted, then add garlic thyme. and saute for about 1-2 minutes, or just until the garlic is soft and fragrant.
Turn the heat down to medium-low. Whisk in the heavy cream, then add cream cheese while whisking, until blended. Cook for about 2-3 minutes.
Then add the chicken broth and mix. Throw in the parmesan cheese and stir until melted. Reduce heat to low. Whisking often to make sure everything melts together and to avoid burns. Let it cook for about 4-6 minutes, or until the sauce thickens.
Season the sauce with salt and pepper to taste.
Add drained pasta, followed by spinach to the skillet, mix to fully combine all ingredients. Adjust seasonings.
Turn off the heat, return the cooked chicken breasts into the pan and let it soak up some of the sauce.
Serve warm on a plate or bowl with sliced chicken on top.