Bring stock, marinara sauce, spices (if using) to a boil in a large stock-pan. NOTE: If you are using FROZEN not fresh spinach or kale, add before bringing the broth to a boil.
Reduce heat to medium heat and add in tortellini. Cook for 10-15 minutes or until tortellini is cooked through. NOTE: If using FRESH spinach or kale, add the last 5 minutes of simmering.
Serve with Parmesan cheese if desired.
If your tomato sauce is well seasoned you will not need to add any flavoring to your soup. But extra garlic, dried oregano, or red pepper flakes are great optional add-ins to this tortellini soup.Leftover Tortellini Soup can be stored in the refrigerator for up to 4 days. When reheated, you may need to add in additional vegetable stock as the pasta will have absorbed some of the broth.