3 Italian turkey sausage links, casings removed
1 medium onion, chopped
4 garlic cloves, minced
1/4 teaspoon crushed red pepper flakes
6 cups reduced-sodium chicken broth
1 jar (24 ounces) pasta sauce
1 can (15 ounces) crushed tomatoes
2 tablespoons tomato paste
2 teaspoons dried basil
2 teaspoons balsamic vinegar
1 teaspoon dried parsley flakes
1-1/2 teaspoons sugar
1/2 teaspoon dried oregano
1/4 teaspoon salt
1/2 teaspoon pepper
2 cups frozen cheese tortellini
Shredded Parmesan cheese, optional

In a Dutch oven, cook sausage and onion over medium heat until sausage is no longer pink and onion is tender, 5-7 minutes, breaking up sausage into crumbles; drain. Add the garlic and pepper flakes; cook 1 minute longer. Stir in the broth, pasta sauce, crushed tomatoes, tomato paste, basil, vinegar, parsley flakes, sugar, oregano, salt and pepper; bring to a boil.
Add tortellini; cook, uncovered, until tortellini are tender, 3-5 minutes, stirring occasionally. Serve immediately. If desired, top with cheese.