For the creamiest results, the oven is best for reheating mashed potatoes, using low heat with added butter/cream and covering them to prevent drying. The stovetop in a covered pot with liquid works well for quick, even heating, while the microwave is fastest but requires stirring and moisture (like a wet towel) to keep them from getting dry. Always add a splash of milk, cream, or butter and stir during reheating for best texture.
Restaurants prepare the potatoes ahead by boiling and mashing just the potato, then just before serving, it is mixed into boiling cream (or milk or even broth or a combination thereof) to reheat it and make it nice and creamy.
To get those potatoes crisp again, Consumer Reports recommends reheating in a 400-degree oven, covering your potatoes with tin foil until warm, and then removing the cover for a final few minutes to allow the skin to crisp back up.
The Oven Method If you're still not sold on a double boiler, you'll be happy to know you can use the inside of your oven to reheat potatoes just as you would any other type of food. The drawback, however, is that it's not as quick as heating them on the stovetop or in the microwave, taking about 30 minutes to prepare.
You can use an oven or slow cooker to keep make-ahead mashed potatoes warm for up to two hours. After baking the potatoes, reduce the oven temperature to 200°. If you need to free up the oven for other dishes, keep food warm using the slow cooker's warm setting.
Slow cooker method
Just as you can make mashed potatoes in a slow cooker, you can reheat them that way, too. Simply add them into your machine, cover, and set to low. Warm through for two to three hours, stirring occasionally and adding milk, cream, or butter to add moisture if necessary.
Wrapping your potato in a wet paper towel before baking it in the microwave helps steam the potato, and aids in even heating so it won't dry out while cooking.
For a baked potato, reheating it in the oven will give the best results, maintaining a fluffy inside and crispy skin. Wrap it in foil to prevent drying out. If you're short on time, the microwave can work, but the potato might lose some of its texture—microwave in short bursts to avoid overcooking.
Mashed potatoes are delicious on their own, but there's also something wonderful about loading them up with bacon, cheese, and crispy fried onions. Oh, and potato chips on top! Get Ree's Mashed Potato Casserole recipe.
"Hold your mashed potatoes in a bain-marie, or water bath, with a lid on top [and] they stay for hours—days really," Ray said in an interview with Allrecipes while promoting her partnership with Home Chef. The method is oh-so-simple.
Cool completely, store in vac pack bags. Reheat in waterbath, transfer to pan, warm cream butter up, beat into mash with Maurice. Pulse in robocoupe very slightly. If you do this too much it will just split and ruin it.
In the Microwave
To prevent that from happening, cut the potato in half and cover each half with a damp paper towel. Place the potato in a microwave-safe dish and heat for two to three minutes, or until the potato is heated through.
It might come as a surprise to learn that mashed potatoes can actually be made a few days ahead of serving. Not only is this a welcome time saver during busy holidays such as Thanksgiving, but your spuds will turn out creamier and fluffier when prepared in advance.
Things you shouldn't put in a microwave oven
Puncture about four holes in the potato, with the tip of a sharp knife or a fork. This is important, as it allows the steam to escape. Otherwise the potato may explode when you cook it. (Seriously!
Wrapping a potato in foil yields a potato with wet skin. The foil prevents moisture from the potato from escaping, and keeps it close to the skin. If you like a crisp, dry skin (as most of us do), skip the tinfoil.
Scoop the mashed potatoes into a microwave-safe bowl and cover with a damp paper towel. Heat potatoes in 2-minute increments, mixing after each iteration. Repeat the process until the potatoes are heated through and have reached a safe internal temperature of 165°F.
Regular oven or toaster oven
Reheating in the oven is a great way to ensure you keep the crispy skin and don't end up with soggy potatoes. Method: Preheat oven to 400. Arrange cooked potatoes on a baking sheet in a single layer (if desired, line with parchment paper). Cover pan with aluminum foil and place in hot oven.
Unfortunately, the palatability of reheated potatoes is inferior to freshly cooked potatoes partly due to the retrogradation of the potato starch occurring during cold storage, freezing and thawing.
A common mistake when making mashed potatoes is overworking them with a mixer or blender, which releases too much starch and makes them gluey or gummy, but another big error is using cold dairy and butter, which doesn't incorporate well and cools down your potatoes, leading to lumpy or heavy mash instead of fluffy and creamy. Other frequent blunders include not seasoning the cooking water, undercooking or overcooking potatoes, and not properly draining them.
A ricer or food mill is the secret tool restaurants use to get that smooth and creamy texture without any gluey starch. It makes the biggest difference and it is actually so fun to use. Your holiday potatoes will never be the same after this!
Using mealy-textured Russet potatoes ensures they fall apart easily, releasing minimal starch and resulting in ultra-fluffy mashed potatoes. Rinsing off the potato starch both before and after cooking ensures fluffy, not gluey, mashed potatoes.