This recipe is part of our street food menu.
Preheat oven to 350°. In a large bowl, whisk together 2 tablespoons oil, cumin, 1 teaspoon sugar, paprika, pepper, cinnamon, turmeric, cloves, mace, and 1 teaspoon salt. Add sweet potatoes, toss to coat, and arrange on a large baking sheet in a single layer. Roast, tossing occasionally, until just tender, about 30 minutes.
Meanwhile, if pepitas aren't already toasted, toss with 2 teaspoons oil and place on a baking sheet; toast in the oven, tossing occasionally, until just crisp, about 10 minutes.
Melt butter in a large, deep skillet over medium-high heat. Stir in remaining 3 tablespoons sugar and cook for 1 minute. Add roasted sweet potatoes, popcorn, pecans, and pepitas; salt to taste. Cook, stirring often, until glazed and heated through, 4 to 5 minutes. Transfer to plates, top with sour cream, and serve immediately.