FOR THE DRESSING (double for a more generous portion):
1/2cupplain nonfat Greek yogurt
3tablespoonsfreshly squeezed lemon juice
1teaspoonpure maple syrup or honey
1/8teaspoonground chili powderplus additional to taste
Place a rack in the center of your oven and preheat the oven to 400 degrees F. Spread the cashews onto an ungreased baking sheet. Place in the oven and toast until the cashews are golden and fragrant and the centers are golden-tan when broken in half, about 8 to 10 minutes. Do not walk away during the last few minutes of baking and set a timer. Nuts love to go from almost done to burned when you stop paying attention. Set aside to cool. Move the oven racks to the upper and lower thirds of the oven and leave the oven preheated.
Meanwhile, rinse and drain the chickpeas, then spread them onto a double layer of paper towels. Place a second towel on top and pat dry. Rub the towel lightly over the chickpeas to dry them and remove any skins that come loose (but don't stress above removing them all). Transfer the chickpeas to a very large mixing bowl.
To the bowl, add the cauliflower, sweet potato, olive oil, curry powder, chili powder, salt, and turmeric. Toss to coat the vegetables until the oil and spices are as evenly distributed as possible.
Lightly coat two large rimmed baking sheets with nonstick spray. Divide the vegetables between the two sheets, spreading them into an even layer. Place the pans in the upper and lower thirds of the oven. Roast for 15 minutes, then remove the pans from the oven. With a large spatula, carefully toss the vegetables, then spread them back into an even layer. Return the pans to the oven, switching their positions on the upper and lower racks. Continue baking until the vegetables are tender and the chickpeas are golden and crisp, about 10 to 15 additional minutes.
While the vegetables bake, make the dressing. Stir together the Greek yogurt, lemon juice, maple syrup, curry powder, salt, cumin, garlic powder, and chili powder.
Assemble the salad: Either in a large bowl (or directly on the baking sheets), stir the roasted vegetables together with the raisins, cashews, and cilantro. Pile onto a serving plate and drizzle with desired amount of dressing. Enjoy warm or at room temperature.