Cook the Beans: Drain the soaked beans and place them in a large pot with 2 quarts / 2L of water, the halved onion, crushed garlic, and bay leaf.
Bring to a boil, then reduce the heat and simmer for 30 minutes.
Add 2 teaspoons (10 ml / 0.3 fl oz) of salt and continue to simmer for another 30-45 minutes until the beans are just tender.
Remove and discard the onion, garlic, and bay leaf.
Do not drain the beans; reserve the flavorful broth.
Start the Soup Base: While the beans cook, heat the olive oil in a large Dutch oven or soup pot over medium heat.
Add the chopped onion, carrots, and celery with a pinch of salt.
Cook, stirring, for 5 minutes until they begin to soften.
Build the Flavor: Add the parsley and leeks, cooking for another 3 minutes until the leeks wilt.
Stir in the minced garlic and cook for 30-60 seconds until fragrant.
Pour in the canned tomatoes and their juice, add the thyme, and season with salt.
Simmer for about 10 minutes, stirring occasionally, until the tomatoes have cooked down.
Combine and Simmer: Pour the cooked beans and all of their savory broth into the pot with the tomato base.
Add the diced turnips and the Parmesan rind.
Bring to a simmer, then cover, reduce the heat to low, and cook for 45-60 minutes until the beans are fully tender and the flavors have melded.
Finish and Serve: Remove and discard the Parmesan rind.
Season the soup with salt and freshly ground black pepper to taste.
Stir in the pasta and cook for 5-10 minutes, or until al dente.
Serve hot, topped with a generous amount of freshly grated Parmesan cheese.
Seasonal Swaps: Clean out your veggie drawer! In winter, add diced butternut squash or chopped kale. For a taste of summer, stir in fresh green beans, peas, or diced zucchini during the last 15 minutes of cooking.
