1/4 pound smoked hot beef and pork sausage (about 2 links), cut into 1/2-inch pieces
1/2 teaspoon Worcestershire sauce
1 pound sweet potatoes
3 scallions, chopped
Garnish: chopped scallion greens
Directions
In a 4-quart saucepan simmer beans, garlic, bay leaf, allspice, broth, and 5 1/2 cups water, partially covered, until beans are tender, about 50 minutes. Discard bay leaf. In a blender purée 1 cup beans with 1 cup cooking liquid and return to pan.
In a small bowl stir together tomato paste and remaining tablespoon water and stir into beans with sausage and Worcestershire sauce. Simmer soup, covered, 15 minutes. Soup may be prepared up to this point 3 days ahead, cooled, uncovered, and chilled, covered.
While soup is simmering, peel sweet potatoes and cut into 1/2-inch pieces. In a steamer set over boiling water steam potatoes, covered, until tender, about 10 minutes. Stir potatoes, scallions, and salt and pepper to taste into soup.