Cannellini beans give this stew a creaminess and body that will make you forget all about the carbs. If you can't sit around the house for three hours (and who can, really?), you can try using a slow cooker, or soak the dried beans overnight.
The key to making this stew something really special though, is to make your own stock. But, if you must use store-bought, make sure to get the low-sodium variety. You'll be cooking this stew for a long time, which means that any salt already present will concentrate.
Soak the beans for at least 4 hours in enough water to cover.* Store in a cool place. Discard any floaters and drain the beans. Place the beans in an 8-quart stockpot and add the chicken stock and sage leaves. Crush 3 cloves garlic and add them in. Season with salt and pepper, to taste. Bring to a simmer over medium heat, and cook for about 2 ½ hours, until the beans are tender. Stir occasionally.
Meanwhile, heat the oil in a sauté pan over medium-high heat. Add the chicken, and brown for five minutes, or until cooked through. Turn the pieces over with tongs about halfway through. Remove and set aside.
In the same pan you cooked the chicken in, over low heat, and add the onions, celery, and carrot. Chop the remaining garlic, and add it in with the thyme. Scrape up any brown bits on the bottom with a wooden spoon. Season with salt and pepper, to taste. Cook, for about 20 minutes or until the vegetables are crisp tender. Stir occasionally. Set aside.
When the beans are done, add the reserved vegetables and the kale. Turn the heat up to medium-high. Cook the kale until tender, about 15 minutes. Return the chicken to the pot and serve.