Stir in meatballs, carrots and broth; bring to a boil. Reduce heat; simmer, covered, 5 minutes. Stir in beans and escarole; return to a boil. Reduce heat; simmer, covered, until escarole has wilted, about 10 minutes. If desired, top servings with basil.

Freeze option: Freeze cooled soup in freezer containers. To use, partially thaw in refrigerator overnight. Heat through in a saucepan, stirring occasionally.