This casserole is a proper Deep South jolt of sweetness from the two cooks who wrote the book on Southern cooking, but with an elegance in textures that the marshmallowy version (all due respect) lacks: a thick layer of craggy pecans and brown sugar on top of smooth, whipped sweet potatoes. Adapted slightly from The Gift of Southern Cooking by Edna Lewis & Scott Peacock. —Food52
Preheat the oven to 350°. Spread the sweet potatoes on a rimmed baking sheet and bake for about 1 1/2 hours, or until tender. Let cool slightly, about 10 minutes, then peel.
In a large bowl, beat the hot sweet potatoes on low speed. Beat in the butter. Add the granulated sugar, brown sugar, honey, vanilla, salt and nutmeg and beat until blended. Add the eggs and beat on medium speed for 2 minutes. Reduce the speed to low and gradually add the hot milk.
Preheat the oven to 375° F. Butter a 13- by 9- by 2-inch baking dish and pour in the sweet potatoes; spread in an even layer.
In a bowl, rub together the flour, brown sugar, cinnamon, nutmeg and salt. Add the butter and rub or cut it in until the mixture resembles coarse meal. Stir in the pecans.
Sprinkle the topping evenly over the potatoes and bake for 1 to 1 1/4 hours, until the topping is golden brown and crisp. If the topping browns too quickly around the edges before the center is crisped, cut a large hole in the center of a sheet of foil and rest it on the dish while it finishes baking. Serve hot.
MAKE AHEAD: The puréed sweet potato mixture and the topping can be refrigerated separately for up to 1 day. Bring to room temperature before proceeding.