[header] How to use leftover sweet potato casserole [title] Make waffles. [step] Create a flavorful waffle batter using basic ingredients and leftover sweet potato casserole. If your casserole is heavily spiced, you'll only need to add milk, eggs, butter, and baking powder. 
Cook the waffles on a hot waffle iron and serve them right away. [substeps] You can top the waffles with chopped pecans or whipped cream.