In a large skillet over medium-high heat, brown the sausage and onion. Cook until no pink remains. Drain excess fat and add to a 6-quart Crock Pot.
Add spinach, diced tomatoes, tomato paste, cream cheese, Italian seasoning, thyme, garlic, tortellini, and chicken broth. Mix until well combined.
Cover and cook on low for 2½ - 3½ hours. Add parmesan cheese and gently. Cover and continue to cook for 10 minutes.
Serve while hot, and enjoy!
