Saute bacon in a medium saucepan. When bacon is almost cooked through, add chopped onion and cook for an additional 5 minutes. When onion is translucent and soft, add the beans, chicken broth and bay leaf. Simmer gently for about 10 minutes. Remove bay leaf and gently smash some of the beans so that the texture is creamy with about half of the beans intact and not smashed. Test for taste and add salt and pepper if needed.