– 1 tablespoon olive oil – 1 small onion, chopped – 1 large carrot, chopped – 2 stalks celery, sliced – 2 cloves garlic, minced – 1/4 teaspoon dried marjoram – 1/4 teaspoon dried parsley flake – 1/4 teaspoon dried thyme – 5 cups chicken broth – 4 (14.5 ounce) cans butter beans, drained – 1 tablespoon distilled white vinegar – 1/2 teaspoon salt – 1/4 teaspoon ground black pepper