black bean pumpkin soup

INGREDIENTS

• Three 15 1/2 ounce cans black beans (about 4 1/2 cups), rinsed and drained
• 1 cup drained canned tomatoes, chopped
• 1 1/4 cups chopped onion
• 1/2 cup minced shallot
• 4 garlic cloves minced
• 1 tablespoon plus 2 teaspoons ground cumin
• 1 teaspoon salt
• 1/2 teaspoon freshly ground black pepper
• 1/2 stick (1/4 cup) unsalted butter
• 4 cups beef broth
• a 16-ounce can pumpkin puree (about 1 1/2 cups)
• 1/2 cup dry Sherry
• 1/2 pound cooked ham, cut into 1/8-inch dice
• 3 to 4 tablespoons Sherry vinegar