This sweet potato casserole is sprinkled with a nutty crumb topping to create a pleasantly crunchy contrast to the creamy and soft mashed sweet potatoes down below. The filling gets an extra special pumpkin pie(ish) treatment with brown sugar and vanilla for a deep caramel flavor. (In fact, leftovers can be heated up and topped with a scoop of ice cream just like pie.) Want to make ahead for Thanksgiving or another special holiday? Not a problem. The casserole ingredients can be mixed and transferred to a baking dish. Cover and refrigerate until ready to bake but leave off the topping. Store it separately at room temperature in an air-right container and sprinkle it on right before baking.
For a velvety smooth filling, ensure sweet potatoes are cooked until incredibly tender before mashing thoroughly, perhaps even passing through a food mill or ricer. For a more rustic texture, a simple potato masher is sufficient. To elevate the flavor profile, consider adding a pinch of ground cinnamon or nutmeg to the sweet potato mixture, or a touch of orange zest for brightness. When preparing the crumb topping, mix only until just combined to maintain a delightful crumble; overmixing can lead to a pasty texture. This dish holds well for make-ahead preparations; keep the topping separate until baking to ensure its crispness. Serve warm, and for an extra indulgence, a scoop of vanilla bean ice cream or a dollop of crème fraîche is excellent.