How to Make It
Heat oven to 375° F. Oil a shallow 2 ½- to 3-quart baking dish.
In a large bowl, toss the sweet potatoes with the Parmesan, 2 tablespoons of the oil, 1 teaspoon salt, and ¼ teaspoon black pepper; transfer to the prepared baking dish. Cover tightly with foil and bake until tender, 45 to 50 minutes.
Meanwhile, in a small bowl, combine the pecans, sugar, thyme, cayenne, the remaining tablespoon of oil, ¼ teaspoon salt, and ⅛ teaspoon black pepper.
Remove the foil from the baking dish, sprinkle the pecan mixture over the potatoes, and continue to bake, uncovered, until the pecans are toasted, 10 to 12 minutes.