Preheat the oven to 400°F and prepare a large baking sheet with parchment paper. Toss the cubed sweet potato with a drizzle of olive oil, salt, and pepper, then spread evenly on the baking sheet. Roast for about 20 minutes until tender and golden. Thinly slice the radish into rounds using a mandoline, and shave the carrots into ribbons with a vegetable peeler. Combine the radish slices, carrot ribbons, and shredded cabbage in a bowl and brighten with a squeeze of lemon juice. In a separate bowl, place the chopped kale leaves, add a squeeze of lemon and a generous pinch of salt, then massage with your hands until the leaves are soft and reduced in volume by half. To serve, arrange the brown rice, chickpeas, kale, carrots, radishes, cabbage, sweet potatoes, sauerkraut, and sesame seeds in individual bowls. Add microgreens if desired, season with salt and pepper, and accompany with the Turmeric Tahini Sauce.