PSA: I’ve rewritten the mashed potato rules. From here on out, making them will be so much faster and easier.
This all came about when I started to question some of the de facto steps I’ve been following for years. Namely: Cutting the spuds into chunks and starting them in cold water.
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The tricky thing with cooking thick potato pieces is that by the time they’re tender at the core, the outside layer has turned to mush and sloughed off starch that makes the mash gluey. The cold-water start is supposed to mitigate this, but in exchange you have to cook the potatoes as gently as possible so that the exterior doesn’t get blown out while you wait for the interior to cook through. Besides, it’s a bit of a slog: Bringing a big pot of water and chunked potatoes to a boil, and then simmering them, takes the better part of an hour.
Here’s the news: Slice the potatoes thin! Add them to boiling water! Use a smaller pot! These changes will drastically simplify and speed the process. Here’s a breakdown of how it works.
How to Make 15-Minute Mashed Potatoes
Use Sliced Potatoes
Thicker pieces invariably overcook at the surface and release loads of sticky gel while you wait for their insides to soften, leading to a gluey mash. Thin-sliced potatoes are virtually all surface area so there’s almost no disparity between the interior and exterior, and the cook time is minimal.
Use Less Water, Smaller Pot
Chunky potatoes take up a lot of space in a pot; sliced ones fit snugly in a smaller pot that holds less water. The upshot: Less time spent waiting for water to boil and cooking the potatoes.
Start in Boiling Water
Starting chunked potatoes in cold water is an attempt to minimize how much their exteriors overcook by the time their centers soften. It’s much easier to start with thin-sliced potatoes and add them to boiling water; they’ll cook quickly and evenly from edge to edge.