Combine the vinegar, sugar, 1 teaspoon kosher salt, 1/4 teaspoon pepper, caraway, mustard seeds, juniper berries and shallots in a medium saucepan. Bring to a boil and cook until the sugar and salt are dissolved. Remove from the heat and strain into a small bowl, discarding the solids.
Preheat the grill to high.
Brush the radicchio with canola oil and season with salt and pepper. Grill cut side down until golden brown and slightly charred, 2 to 3 minutes per side. The radicchio should not be cooked all the way through, but retain some bite. Remove from the grill, thinly slice and put in a bowl.
Remove the kale from the water and shake gently to get some of the water off (any excess water will help it steam while grilling). Season with salt and pepper and place on the grill. Grill until slightly wilted and charred on all sides, about 1 minute per side. Remove, thinly slice and add to the radicchio. Add some of the vinegar mixture and toss to coat. Toss again with olive oil, salt and pepper. Taste, and add more vinegar if desired. Let sit at room temperature for 30 minutes to allow the flavors to meld.