Roast the Sweet Potatoes and Onions: Preheat your oven to 400°F (204°C). On a large baking sheet, arrange the halved sweet potatoes cut side down and the red onion wedges in a single layer. Drizzle them evenly with about half of the oil, making sure the sweet potatoes are well coated. Roast for 10 minutes to start softening and caramelizing the vegetables.
Add Broccolini and Continue Roasting: After 10 minutes, carefully flip the sweet potatoes so the skin side is down. Scatter the chopped broccolini onto the baking sheet around the potatoes and onions. Drizzle the broccolini with a little oil and season with salt and pepper. Return the sheet to the oven and roast for another 8 to 10 minutes until the broccolini is tender and the potatoes are nicely browned.
Roast the Kale for Crispiness: Remove the baking sheet again and add the kale on top of the other veggies. Lightly drizzle with remaining oil and season with a pinch of salt and pepper. Roast for an additional 4 to 5 minutes, just until the kale starts to crisp but doesn’t burn. Remove from the oven and set the vegetables aside.
Prepare and Sauté the Chickpeas: While the vegetables roast, combine the chickpeas in a medium bowl with the cumin, chili powder, garlic powder, salt, pepper, oregano, and turmeric (if using). Toss well to evenly coat. Heat a large skillet over medium heat and add 1 tablespoon of oil. Add the seasoned chickpeas and sauté, stirring often, for about 10 minutes until they become golden brown and crispy. Adjust the heat as necessary to avoid burning or undercooking. Remove from heat.
Whisk the Tahini Maple Dressing: In a small bowl, whisk together the tahini, maple syrup, and lemon juice. Slowly add hot water, a tablespoon at a time, whisking continuously, until the sauce reaches a smooth, pourable consistency. Set aside.
Assemble the Buddha Bowls and Serve: Slice the roasted sweet potatoes into bite-sized pieces. Divide the roasted vegetables evenly among three bowls. Top each with a generous portion of crispy chickpeas, then drizzle with the tahini maple dressing. Serve immediately for best flavor and texture.