In a large pot, heat sun-dried tomato (2 tablespoons) oil over medium heat, until it's heated and is shimmering. Add chopped onion (1 1/2 cups) and sauté, stirring occasionally, until it's translucent. Add garlic (1 heaping tablespoon) and continue to sauté, stirring frequently, until fragrant, about 1 minute.
Stir in tomato paste (1/4 cup) and sun-dried tomatoes (1/2 cup) to onion mixture and cook, stirring constantly, until tomato paste is slightly deeper red in color, about 2 minutes.
Stir in broth (72 ounces), diced tomatoes with their juices (1 can), salt (2 teaspoons), Italian seasoning (1 tablespoon), dried rosemary (2 teaspoons), garlic powder (1 teaspoon), and crushed red pepper (1/2 teaspoon) and bring to a boil, over medium, stirring occasionally, about 12 minutes.
Stir in softened cream cheese (8 ounces), parmesan cheese (1 cup), cooked chicken (4 cups), and pasta (8 ounces) and cook, stirring and scrapping the bottom of the pot, until pasta is al dente, about 12-18 minutes.
Add cream (1 cup) and cook until heated. Stir in spinach (6-8 cups) and cook until spinach is wilted.
Remove from heat and stir in basil (1/2 cup). Taste and adjust seasoning if needed. Ladle into individual bowl, pass extra parm on the side, and serve.