2 cups dried chickpeas
1 carrot, peeled and cut into large chunks
1 celery stalk, cut into large chunks
1 onion, peeled and halved
11 garlic cloves
5 strips lemon peel
1 rosemary sprig
1 tablespoon kosher salt, or more to taste
3 quarts water
~1/2 cup olive oil (this is toned way down — if you want the full effect, throw in a full cup with the cooking beans)
¼ teaspoon dried chili flakes
2 bunches Tuscan kale
Freshly cracked black pepper
Finely grated Parmigiano-Reggiano
Place the chickpeas in a large bowl and cover with plenty of water and a hefty spoonful of salt. Let soak for 8 hours or overnight, then drain.
Wrap the carrot, celery, onion, 3 garlic cloves, the lemon peel, and rosemary in a large square of cheesecloth and secure with kitchen twine or a tight knot. Place in a large pot with the soaked and drained chickpeas, the additional salt, the water, and 1/4 cup of the olive oil (alternately, if you don't want to deal with cheesecloth, you can just float all the aromatics in the broth, and fish them out later). Bring to a boil over high heat, then reduce the heat to medium-low and simmer until the chickpeas are tender, about an hour. Add more water if needed to cover.
While the chickpeas are cooking, finely chop the remaining 8 garlic cloves. In a large skillet, heat 2 tablespoons olive oil over medium heat. Add the garlic and chili flakes and cook until the garlic is fragrant but not golden, about 1 minute. Remove from the heat, and transfer the garlic to a blender or food processor.
Remove the center ribs from the kale (or not, if they're not too fibrous) and coarsely chop the leaves. In the same skillet you used for the garlic, heat a few tablespoons of olive oil over a medium-high heat. Add enough kale to fill the skillet, and cook, tossing, occasionally, until tender (~3 minutes). Remove, and transfer to the blender or food processor with the garlic. Repeat with the remaining batches of kale until it's all cooked, adding more oil to the pan if needed.
When the chickpeas are cooked, add 2 cups of them to the blender along with the kale and garlic, and a cup or so of cooking liquid. Puree until smooth. Return the puree to the pot and cook over medium-high heat until hot. Season with salt and pepper to taste.
Ladle the soup into bowls. Finish with a squeeze of lemon and some grated Parmigiano-Reggiano.