A smart way to repurpose sweet potato casserole, this hearty soup drew rave reviews in our Test Kitchen. If your casserole contains marshmallows, remove them before stirring the casserole into this soup. The flavor will vary depending on your casserole recipe; simply adjust salt and pepper to taste before serving.
Cook sausage in a Dutch oven over medium heat, stirring occasionally, 7 to 8 minutes or until browned. Remove sausage from Dutch oven, using a slotted spoon. Reserve 2 Tbsp. drippings in Dutch oven.
Sauté onion in hot drippings in Dutch oven over medium-high heat 5 to 6 minutes or until tender. Add garlic, and sauté 2 minutes. Add broth, next 3 ingredients, and cooked sausage; bring to a boil. Reduce heat to medium, and simmer 20 minutes.
Add kale, and simmer 5 minutes. Add salt and pepper to taste. Serve with crackers.