Preheat your oven to 425 degrees F. Line a large rimmed baking sheet with parchment paper and set it aside.

Scrub the sweet potatoes well. Peel them if the skin is rough or thick. Cut each potato in half lengthwise, then cut each half into wedges about 1/2 inch thick. Try to keep the pieces close to the same size so they roast evenly.

Spread the wedges on a clean kitchen towel or several layers of paper towels and pat them dry. Surface moisture is what prevents crispy edges, so take an extra 30 seconds here. It makes a real difference.

Transfer the dried wedges to a large mixing bowl. Drizzle with olive oil and toss to coat. Sprinkle in the chili powder, garlic powder, cumin, salt, and pepper. Toss again until every wedge is evenly coated with the seasoning.

Spread the wedges in a single layer on the prepared baking sheet. Give them space. Overlapping wedges steam each other instead of roasting. Use a second baking sheet if needed.

Roast at 425 degrees F for 15 minutes, then flip each wedge with a spatula or tongs. Return the pan to the oven for another 12 to 13 minutes. The wedges are done when the edges look firm and lightly caramelized, and a fork slides in easily at the thickest part.

Pull the pan from the oven and squeeze both lime halves over the hot wedges immediately. Scatter fresh cilantro on top if using. Serve right away for the best texture.