The traditional sweet potato casserole with sticky sweet marshmallows on top is a classic favorite at Thanksgiving dinner tables. This re-imagined version brings it to a whole new level with a pecan crumble for texture as well as a sweet and fluffy brown sugar meringue piped on top. If you don’t like your sweet potato casserole candy sweet, just skip the meringue topping and bake it with the pecan crumble alone.