Preheat your oven to 400°F and line a large baking sheet with parchment paper. Toss the cubed sweet potato with a drizzle of olive oil, a sprinkle of sea salt, and freshly ground black pepper. Spread them evenly on the prepared baking sheet and roast for about 20 minutes, or until they turn golden and tender.
Meanwhile, use a mandoline to thinly slice the radishes into delicate rounds, and peel the carrots into long ribbons using a vegetable peeler. Combine the radish slices, carrot ribbons, and shredded red cabbage in a bowl, and toss them with a generous squeeze of fresh lemon juice. Set this vibrant mixture aside.
In a separate large bowl, place the chopped kale leaves. Squeeze a bit of lemon juice over the kale, add a pinch of salt, and massage the leaves with your hands. Continue until the kale softens, wilts, and reduces in volume by about half.
To assemble the bowls, start with a base of cooked brown rice or quinoa, followed by a portion of chickpeas or lentils. Add a handful of the massaged kale, a serving of the lemony radish, carrot, and cabbage mixture, and a generous scoop of the roasted sweet potatoes. Top it off with a spoonful of sauerkraut, a sprinkle of sesame seeds or hemp seeds, and some microgreens if desired. Finally, season with additional salt and pepper to taste, and serve with a side of Turmeric Tahini Sauce for drizzling over the top.