Part of the beauty of minestrone is how versatile it is. The entire idea of the recipe is to use what you have on hand. I personally find it is easiest to procure dried red kidney beans, but any bean or pulse will do. Just be sure to know the cook time of whatever dried bean you opt to use. Canned beans (or lentils) are also perfectly acceptable. Be sure to drain them and rinse them in water before adding to the soup. If you are concerned about salt consumption, it is better to rinse the canned beans prior to adding them. Add about 1.5 cups of preferred choice of canned beans. Be sure to drain them and rinse them in water before adding to the soup. Do a taste test first as sometimes canned beans can be bitter. If they are bitter discard them.