Turkey Sausage, Spinach and White Bean Soup

Lady has been making this soup for a long time and I love it. It is such a delicious yet easy soup. The butter adds richness but this soup can also be altered to be a very healthy soup. Just leave out the butter.

Turkey Sausage, Spinach and White Bean Soup
8 oz. Italian turkey sausage (removed from casings)
1 teaspoon extra virgin olive oil
5 garlic cloves, minced
1/2 teaspoon crushed red pepper flakes (I use 1 teaspoon)
20 ounces fresh spinach
2 (15oz.) cans cannellini beans, NOT DRAINED
4 cups chicken broth
1/4 cup unsalted butter
1/2 cup freshly grated parmesan cheese
3 plum tomatoes, diced
1/4 teaspoon salt
1/4 teaspoon freshly ground black pepper

Brown sausage in hot oil in a dutch oven over medium-high heat until cooked through. Add garlic and red pepper flakes and saute 2 minutes. Add spinach and saute until wilted. Add beans, broth and butter. Bring to a boil. Add salt and pepper to taste and add tomatoes and cheese before serving.