In a 5-6 qt. large stock pot or dutch oven heat the olive oil on medium high heat. Add the onions and cook for about 15 minutes- or until soft and golden. Add the garlic and cook for another few minutes.
Add the beans, broth, rosemary, salt & pepper. Bring to a boil, and then simmer for about 20 minutes. Use an immersion blender, food processor, or regular blender to purée the soup until smooth. Add cayenne pepper to taste. Top with crispy bacon.
Recipe adapted from: The Food Network