Leftover sweet potato casserole can be reheated as a side, or the filling can be turned into a breakfast. Only use leftovers that were refrigerated within 2 hours and are still within 3 to 4 days, unless a specific food has a different USDA window. Reheat mixed dishes to 165°F. See how long leftovers last and USDA leftover guidance. If the leftover casserole has a marshmallow or pecan topping, decide whether you want that topping in the new dish; sometimes it is better to scrape filling from underneath and use the topping only when you reheat a straight leftover portion.
Reheat a portion
Spoon leftover casserole into a small dish, cover it, and warm it in a 325°F to 350°F oven or in the microwave until the center reaches 165°F. If the topping was marshmallows, they will melt again; add a few fresh ones at the end if you want a new toasted top. If it was a pecan streusel, cover the dish so the nuts do not scorch, then uncover briefly if you want more crunch.
Waffles, pancakes, or a breakfast bake
For a different breakfast, scoop leftover sweet potato filling, leaving behind a very sticky topping if needed, and loosen it with an egg and a little milk or flour until you have a thick batter. Cook it as waffles or pancakes until they are cooked through and any leftover filling is hot. You can also spoon leftover casserole into a small buttered dish, add a couple of eggs on top if you want a savory-sweet bake, and heat it until the eggs are set and the sweet potatoes are at 165°F. Do not treat this as a dessert that can sit out; it is still a leftover that needs refrigeration.
Storage
Keep leftover sweet potato casserole in a covered shallow container and use it within 3 to 4 days, or freeze portions if you will not get to them. Quality varies once a marshmallow topping has been frozen and thawed. Reheat frozen leftovers to 165°F. For related dessert leftovers, see what to do with leftover pumpkin pie. More leftover pages are in the leftovers guide.
Helpful kitchen tools
- Pyrex Deep 9×13-Inch Glass Baking Dish with Lid — A small lidded dish is useful for reheating a portion of leftover casserole.
- TempPro TP19H 1-Second Digital Meat Thermometer — Check that the leftover casserole reaches 165°F when you reheat it.
- OXO Good Grips Bent Icing Spatula — Helps you scoop leftover filling without taking the entire topping in one clump.
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Frequently asked questions
Can I turn leftover sweet potato casserole into waffles?
Yes, if you loosen the filling with egg and a little milk or flour and cook the waffles through until they are hot in the center.
What about the marshmallow topping?
It will melt when you reheat the casserole. For waffles or a bake, you may want to use filling from underneath the topping.
How long does leftover sweet potato casserole last?
Use it within 3 to 4 days in the refrigerator if it was packed and chilled on time, and reheat it to 165°F.