Heat the olive oil in a large pot over medium heat. Add the onion and sun-dried tomatoes. Cook for 3 to 5 minutes until the onion softens.
Stir in the garlic and cook for 1 minute.
Pour in the chicken broth and heavy whipping cream. Stir to combine.
Add the cream cheese and Parmesan. Stir continuously until the cheeses melt and the broth becomes creamy.
Add the orecchiette, salt, black pepper, and red pepper flakes. Stir well.
Cover and cook for 14 to 16 minutes, stirring occasionally, until the pasta is tender.
During the last 5 minutes of cooking, stir in the rotisserie chicken so it heats through. In the final minute, add the spinach and cook just until it wilts.
Ladle into bowls and top with extra grated Parmesan. Serve hot.