Heat the oil in a large saucepan over medium heat. Add the sausage and brown for 2 minutes. Add the onions and peppers, season with salt and pepper, and cook, stirring, until the vegetables are soft, 3 to 4 minutes. Stir in the garlic and black beans, and cook for 1 minute. Add the stock and bring the mixture to a boil, reduce the heat to medium-low and simmer until the beans are creamy and tender, about 2 1/2 hours, stirring occasionally. Stir in the butter and reseason with salt and pepper.
Yield: 8 to 10 servings