Move oven rack to the top middle position and turn on broiler to high.
Pour hot water over ¼ cup raisins in a small bowl. Soak for at least 15 minutes, up to several hours, until they are plump. Drain and discard leftover water.
Whisk together 2 Tablespoons red wine vinegar, ½ teaspoon kosher salt, and ¼ teaspoon freshly ground black pepper in a large bowl. Continue whisking while adding 2 Tablespoons olive oil in a slow, steady stream. Add 2 cups arugula or mizuna, the chopped kale, and shredded beets, and toss to coat.
Transfer dressed greens to a medium skillet, lightly packing them in if needed. Sprinkle ½ cup shredded Parmesan cheese evenly over the top of the greens and place under the broiler until cheese is melted and beginning to brown, and greens are wilted, about 5 minutes.
Top the wilted greens with the soaked raisins and ¼ cup chopped toasted hazelnuts. Drizzle with 1 teaspoon Balsamic vinegar. Serve immediately.