Grate the ginger (no need to peel!) with either a box grater or microplane, and add it to a medium bowl. Rinse and halve the lime. Add the juice from ½ the lime, 2 tbsp water, the chia seeds, maple syrup, and miso paste to the bowl. Whisk the ingredients together to combine and set aside.
Preheat your oven to 425 °F. In a small pot, combine 1 ¾ cups water, a couple pinches of salt, and the black rice over high heat. Bring to a boil, cover, and reduce heat to a simmer. Cook until the rice is tender and the water is absorbed, about 25 minutes.
Rinse and peel the yam. Cut into ½-inch cubes. Place yam on one half of a baking sheet, and spread the pumpkin seeds on the other. Toss the yam with 2 tsp oil and season with salt and pepper. Toss the pumpkin seeds with 1 tsp oil and the cayenne. Bake until seeds are toasted, about 8 to 10 minutes. Transfer the seeds to a plate, and continue to cook the yams until tender, about 10 to 15 minutes.
Rinse and destem the cauliflower. Slice the florets into ¼-inch thick pieces. Place a medium skillet over medium-high heat with 1 tbsp oil. When the pan is hot add the cauliflower and cook until caramelized and tender, about 5 to 7 minutes. Season with salt and pepper, nutritional yeast, and squeeze the remaining half lime on top.
Rinse, dry, and destem the kale. Discard the stems and stack the leaves. Thinly slice the leaves. Add the sliced kale to the bowl with the ginger-chia dressing, and use your hands to gently massage the kale for 1 to 2 minutes. Season with a pinch of salt and pepper.
Divide the black rice between your bowls, and top with the kale, roasted yams, and sauteed cauliflower. Drizzle with any of the ginger-chia dressing left in the bottom of the kale bowl, and top with cayenne pumpkin seeds. Eat up, and power up!