Soak the beans. Soak them in cold water overnight. Or use this quick-soak method. In a large pot, combine beans and cold water (6 cups water for each pound of beans—we used 4-1/2 cups for our 12 ounces of beans). Bring to a boil and cook for 2 to 3 minutes. Turn off heat, cover pot and soak beans for at least an hour).
Start the broth. Poke the cloves into the peeled whole onion. Put the onion, the ham hock, bay leaves and thyme into a large Dutch oven or stock pot. Add 3 to 3-1/2 quarts of water to the pot, enough to cover the ham hock (or very nearly—you can turn the hock occasionally as it cooks). Bring to a boil, then reduce the heat and simmer, covered, for 1 hour.
Meanwhile, as you near the end of that hour of broth cooking, melt the butter in a large skillet over medium-high heat, then cook the carrots, turnip, leek and minced garlic for 5 to 7 minutes, stirring frequently to avoid overbrowning the leek.
Add the vegetables and the drained white beans to the broth, and simmer for 1 hour, covered.
Next, add the shredded savoy cabbage and simmer for 30 minutes, covered.
Stir in the potatoes and simmer at least another 30 minutes, until they are quite tender. When you add the potatoes to the pot, you can cover it or leave it uncovered, depending on how much liquid remains—we chose to let the broth cook down a bit.
Transfer the hock from the broth to a cutting board. Let it cool slightly, then remove and discard the outer skin and fat. Remove the now very tender meat from the bones and, working with two forks, shred it. You can also use a sharp knife, but the forks method shreds it beautifully and is so satisfying to do. Return the meat to the pot.
Discard the bay leaves. Remove the cloved onion from the pot. Discard the cloves, chop the onion and add it back to the pot.
Taste and adjust the seasoning with salt and pepper (the smoked hock will add plenty of salt, so season accordingly). At this point, your garbure is ready to serve. But if you can, let it rest a day in the fridge to let the flavors combine and mellow. Your patience will be rewarded. When you serve it, give it a good stir with your ladle as you dish it up, making sure everyone gets plenty of the vegetables and meaty goodness.