1. To start the soup: Drain the beans and return them to the pot. Add the onion halves, the whole carrot, the whole celery stalk, the bay leaf, and potatoes. Add enough fresh water to cover the beans by at least 3 or 4 inches, bring to a simmer, and cook until the beans are soft. Depending on how old the beans are, this could take from 2 to 3 hours. Five minutes before removing from the heat, add salt. Rinse farro and cover, place in a large bowl and cover it with 3 cups cold water. Set aside.

2. With a slotted spoon, remove the beans and potatoes from the cooking liquid. Discard the onion, carrot, celery, and bay leaf, but reserve the liquid. Remove 1/4 of the beans and potatoes and set aside.

3. In a food processor puree the remaining bean/potato mixture with the reserved cooking liquid. Set aside.

4. In the food processor puree the garlic, the chopped onion, chopped carrot, and chopped celery, the leek, pancetta, sage, rosemary, and crushed red pepper to a coarse paste.

5. Coat the bottom of a large stockpot with the ¼ cup olive oil. Add the pureed vegetable mixture and butternut squash and sauté over medium heat until the mixture starts to color, 10 to 15 minutes. Stir frequently to prevent sticking.

6. Add the tomato paste and wine and cook until the wine has reduced by half.

7. Add the bean/potato puree and 1 quart water, season with salt and pepper, and simmer for 25 to 30 minutes, stirring occasionally to prevent sticking.

8. Drain the farro and add it to the soup. Add the reserved beans and potatoes and continue to cook for 40 to 45 minutes, adding 1 quart more water. If the soup becomes dry toward the end of the cooking time, add a little more water. Adjust the seasonings.

9. To serve, drizzle the soup with olive oil and sprinkle with the Parmesan and black pepper.