Once you've cored and thinly sliced the radicchio, place it in a bowl of ice water for at least 30 minutes to soak. This helps take away some bitterness, (although if you like bitter vegetables, it's may not be necessary). After the 30 minute soak, drain and pat the radicchio dry.
Blend the beans with 4 of the garlic cloves and about ½ cup of broth until smooth, adding more broth if necessary to help the process.
In a small saucepan, heat the blended beans with the small amount of broth, stirring a few times, until the liquid reaches just below a simmer. Leave barely simmering.
In a medium or large saucepan, heat the remaining broth, until the liquid reaches just below a simmer. Leave barely simmering. [Note: to cut down on dishes, you could simply add this broth to the saucepan once you've used the bean puree and heat the newly added broth quickly.]
In a large Dutch oven, heat a glug (about 2 tablespoons) olive oil over medium heat. Add the onion and a pinch of Kosher salt to the pan, stirring frequently, until the onion is translucent and fragrant but not browned, about 5 minutes.
Add the sausage to the onions in the Dutch oven and cook, breaking up any large clumps of ground meat, until the sausage loses its pinkness, about 4-6 minutes.
Reduce the heat under the Dutch oven to low, add half the heated pureed beans, and stir to incorporate. The onions and sausage should be coated in a rich, creamy bean puree.
Add the rice and stir to distribute within the Dutch oven. Add the rest of the pureed beans and stir to incorporate. Add a cup of the separately heated chicken broth or bean liquid and stir. Adjust the heat under the Dutch oven to medium/medium-high, so the contents are bubbling but not boiling away like crazy. [You want it to be hot enough to cook properly but not so hot that the liquid evaporates so quickly it doesn't tender the rice.] Stir occasionally, until the liquid is almost entirely absorbed and you see the bottom of the pan when you stir.
Add another cup or so of the heated broth and repeat the stirring occasionally until mostly absorbed process. Continue until the rice is no longer hard or chalky in the core when you bite into it. This should take 18-25 minutes - if it's taking longer, the heat under your rice isn't high enough. If you run out of broth, add some warm water.
While you wait for the rice, take this time to prep the kale, parsley, and cheese. Slice the kale into thin ribbons and saute it with the remaining 2 cloves or garlic for a few minutes. Add the radicchio and continue sauteing for another 2 minutes.
When the rice is done, you'll want a little liquid remaining because the dish firms up with the addition of the cheese and as time goes on. If necessary, add a little broth or water (½ cup) to achieve a loose consistency. Taste for seasoning and adjust with salt and pepper as desired.
Add in the sauteed radicchio and kale plus the arugula and parsley, and fold them into the rice. The heat from the risotto will wilt the greens. Fold in half the grated cheeses and serve immediately, with the remaining grated cheese in a side serving bowl.