Mashed Potatoes That Break the Rules

Forget big pots of water, long simmer times, and gummy mash. Rigorous testing and our best potato science revealed a smarter, faster, more flexible path.

Published Dec. 5, 2022.

Sometimes recipe development presents me with an opportunity to learn a preparation from the ground up—such as with keema, the ground meat curry that’s eaten widely around the Indian subcontinent, or japchae, Korea’s beloved noodle stir-fry. At other times, the R&D process allows me to give a familiar recipe or technique a fresh look. I never know where I’ll end up, but when I challenge my assumptions about the best way to cook something that I’ve made countless times before, I often come away with a smarter method and a whole new understanding of what makes it tick.

New Formula for a Better (and Faster) Mash

OLD RULE: Use whole or chunked potatoes

NEW RULE: 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. But thin-sliced potatoes have more surface area and thus cook evenly from edge to center, so there’s virtually no risk of overcooking them.

OLD RULE: Start in cold water

NEW RULE: Start in boiling water

Starting chunked potatoes in cold water is an attempt to minimize how much of their exterior overcooks by the time the center softens. Since thin-sliced potatoes cook evenly from edge to edge, it’s fine to add them to boiling water.

OLD RULE: Lots of water in a big pot

NEW RULE: Less water in a medium pot

Chunky potatoes take up a lot of space in a pot; sliced ones fit snugly in a smaller pot that holds less water.

OLD RULE: 30 minutes or even longer

NEW RULE: Less than 15 minutes

Besides cooking more evenly, sliced potatoes cook through much more quickly. 

That’s how it went with boiled corn, sautéed mushrooms, turkey gravy, caramel sauce, and most recently, mashed potatoes. After making hundreds of batches over the years, I began to question some of the canonical rules. Namely: Cut the spuds into chunks, and start them in cold water so that their exteriors aren’t overcooked by the time the centers come up to temperature.

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The most exacting recipes even call for a rinsing step to remove starch, which frankly seems like a backwards fix to me. Cooking thick pieces until they’re tender at the core is what causes that mushy outer layer of sloughed-off starch to form in the first place—the same way a large roast grays at the edges while you wait for the middle to come up to temperature. Rinsing away that starch is critical to avoiding a gummy mash, but instead of trying to remedy the situation, why not cook the potatoes more evenly in the first place? Plus, the boiling step is a bit of a slog. Bringing a big pot of water and whole or chunked potatoes to a boil takes a good 15 to 20 minutes, to say nothing of the additional 20 to 50 minutes of simmering time required to cook the potatoes through.

Make Your Favorite Mash

By choosing the right potato, processing tool, and ratio of spuds to dairy, you can customize the mash exactly to your liking. 

Lastly, since there’s no one best style of mashed potatoes, I wanted to come up with options for customizing the flavor and consistency. I could make them earthy or buttery-sweet, chunky or smooth, fluffy or creamy, simply by picking the right potato and processing tool for the job, and adding more or less dairy. 

So after weeks of testing and steeping myself in spud science, I’ve rewritten the rules. This approach will deliver buttery, plush, cohesive—but not gummy—results in less time and offer a range of options for making the mash your own.

Fastest, Easiest Mashed Potatoes

Forget big pots of water, long simmer times, and gummy mash. Rigorous testing and our best potato science revealed a smarter, faster, more flexible path.
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