hands-on Time: 15 minutes
Total time: 1 hour, 10 minutes
3 T olive oil, plus more for the baking dish
2 1/2 lbs sweet potatoes, peeled and sliced into 1/4-inch-thick rounds (You might need a mandoline for this or chop smaller so they cook through.)
1/2 cup grated Parmesan (2 oz)
Kosher salt and black pepper
3/4 cup chopped pecans
1/4 cup light brown sugar
2 t fresh thyme leaves
Pinch of cayenne pepper
Heat oven to 375 F. Oil a shallow 2 1/2- to 3-quart baking dish.
In a large bowl, toss the sweet potatoes with the Parmesan, 2 T of the oil, 1 t. salt, and 1/4 t 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 T of oil, 1/4 t salt, and 1/8 t. 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.