Mashed potatoes are one of the simplest yet best comfort foods and an essential side dish for every holiday table. Previously, we’ve written about how to make the best mashed potatoes, but one of the problems many people have is how to make them ahead of time and reheat them properly. Because of their starchiness, mashed potatoes are notorious for becoming thick and gluey after storing in the fridge and trying to reheat in the microwave or on the stove in a pan. The reason is that once they cool down, the starches in the potatoes tighten up and are difficult to unravel.
Also, the direct heat of a microwave can cause the potatoes to dry out and the stove can cause them to scorch. So, what’s the solution? We need a buffer between the potatoes and the heat to warm them gently and evenly, which for us comes in the place of one simple thing – hot water! By using a hot water bath, either on the stove or in the oven, the direct heat warms up the water which then gently warms the potatoes. No scorching, no drying out. Just perfect, hot, creamy, mashed potatoes.
It may take a little longer than a zap in the microwave but after testing both of the methods below, we’re convinced that mashed potatoes reheated this way are just as good as fresh. Make things easy on yourself and prepare your mashed potatoes a day or two ahead of time. Store them in a airtight container in the fridge and reheat them right before serving.
Method 1: On the Stove
Place a large, deep pot on the stove and fill 1/3 of the way with water. Bring to a boil, then reduce to a very low simmer. Submerge a smaller pot with the cold mashed potatoes into the larger pot so the hot water comes most of the way up the sides. Keep the water on a low simmer and stir the mashed potatoes frequently until warmed through. Add a splash of milk to help thin it out if needed. To hold the mashed potatoes for an hour or two, simply turn off the heat and cover the pot.
Method 2: In the Oven
Preheat the oven to 350 F. Spoon the mashed potatoes into a smaller oven safe dish and cover with foil. Place the mashed potato filled dish into a larger baking dish with high sides and place in the oven. Pour boiling water into the larger dish so it comes halfway up the sides of the smaller dish. Heat for 20-30 minutes (depending on the size of the pan), stirring halfway through.
Either method works equally well, it just depends if you have oven or stove space available. The stove method might be a tad easier since you don’t have to worry about lifting a pan full of boiling water out of the oven, but the rationale behind both is exactly the same. Instead of applying direct heat to the potatoes, you use a hot water bath to gently warm them through.
In order to reheat mashed potatoes, you need to make some first.