Heat a dutch oven over medium high heat. Cook sausage in dutch oven for about 7 minutes until lightly browned. Remove from pot and set aside.
Add onions to dutch oven and sauté for 7 minutes, stirring occasionally.
Add kale, beans, broth, water, red pepper flakes, and salt. Bring to a boil and reduce heat to medium low to simmer. Simmer for 15 minutes.
Add sausage to the soup, and simmer for at least 15 minutes. You can simmer for up to 90 minutes, but add extra water if needed. When ready to eat, serve and enjoy!
Notes
*Makes 6 cups*Any white beans can be used: Great Northern Beans, Cannellini beans, Navy beans. Also, kidney beans, garbanzo beans and pinto beans will work in this soup.*8 ounces of kale is about ½ to ¾ of a bunch of kale.