In a large dutch oven over medium heat, cook bacon until crisp.
Remove bacon and bacon grease, then return 1 tablespoon of the bacon grease to the pot and heat.
Set bacon strips on a paper towel to drain and cool, then crumble.
Add diced onion, celery, carrots and sauté until soft, about 3-5 minutes.
Add the butter beans, broth, bacon and seasonings.
Bring the broth to a boil, and then reduce the heat to a simmer and cook for 45 to 1 hour, or until tender.
Then stir in heavy cream and butter into bean mixture until thickened, about 15 minutes more.
Season with salt and pepper, and top with additional crumbled bacon before serving.