This is an excellent minestrone recipe on a cold winter evening. The soup is rich, smoky-tasting and is good with warmed corn tortillas or corn bread. Black beans, also known as turtle beans, are savory and hold their shape during the long, slow cooking needed for a soup such as this one. Black beans should not be confused with the salty, fermented black soybeans used in Chinese black bean sauce. For deep, rich color, do not presoak the beans for this recipe. COOKS NOTES: Borlotti, cranberry and black beans are available in dried and canned form from larger supermarkets, natural food stores, specialty food shops and on line distributors. The Italian borlotti bean's creamy texture and mellow flavor are delicious in sturdy soups such as this one. The cranberry bean is sometimes marketed as borlotti but is also popular in its own right. As a rule of thumb, 1 cup of dried beans (soaked overnight in water to cover and drained) cooked in 3 cups water yields approximately 2½ cups of cooked beans. You can substitute cooked red, white or kidney beans.